如何禁用/启用对话框的负面肯定按钮?


111

请查看下面的自定义对话框。我在对话框上有一个edittext字段,如果文本字段为空,我想禁用positiveButton。我可以为文本字段获取charListener,但不确定如何positivebutton从该侦听器设置为禁用或启用?正负按钮的参考是什么?

 case DIALOG_TEXT_ENTRY:
    // This example shows how to add a custom layout to an AlertDialog
    LayoutInflater factory = LayoutInflater.from(this);
    final View textEntryView = factory.inflate(R.layout.alert_dialog_text_entry, null);
    return new AlertDialog.Builder(AlertDialogSamples.this)
        .setIconAttribute(android.R.attr.alertDialogIcon)
        .setTitle(R.string.alert_dialog_text_entry)
        .setView(textEntryView)
        .setPositiveButton(R.string.alert_dialog_ok, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {
                /* User clicked OK so do some stuff */
            }
        })
        .setNegativeButton(R.string.alert_dialog_cancel, new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface dialog, int whichButton) {
                /* User clicked cancel so do some stuff */
            }
        })
        .create();
}


谢谢,但这不是答案。它可能会有所帮助。因为它在单击自身后会禁用按钮。这不是我想要的。我想显示它禁用取决于文本字段。
2011年

1
if(editTextEmailAddress.getText()。toString()。length()== 0)
SALMAN

基本上,使用匿名引用创建对象后,就无法再引用它。谢谢。
SALMAN

Answers:


207

编辑以获得完整的解决方案...

AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
builder.setIcon(android.R.drawable.ic_dialog_info);
builder.setTitle("Alert dialog title");
builder.setMessage("This is the example code snippet to disable button if edittext attached to dialog is empty.");
builder.setPositiveButton("PositiveButton",
        new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface arg0, int arg1) {
                // DO TASK
            }
        });
builder.setNegativeButton("NegativeButton",
        new DialogInterface.OnClickListener() {
            public void onClick(DialogInterface arg0, int arg1) {
                // DO TASK
            }
        });

// Set `EditText` to `dialog`. You can add `EditText` from `xml` too.
final EditText input = new EditText(MainActivity.this);

LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
        LinearLayout.LayoutParams.MATCH_PARENT,
        LinearLayout.LayoutParams.MATCH_PARENT
);
input.setLayoutParams(lp);


builder.setView(input);

final AlertDialog dialog = builder.create();
dialog.show();

// Initially disable the button
((AlertDialog) dialog).getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);

// OR you can use here setOnShowListener to disable button at first time.

// Now set the textchange listener for edittext
input.addTextChangedListener(new TextWatcher() {

    @Override
    public void onTextChanged(CharSequence s, int start, int before,
            int count) {
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count,
            int after) {
    }

    @Override
    public void afterTextChanged(Editable s) {

        // Check if edittext is empty
        if (TextUtils.isEmpty(s)) {
            // Disable ok button
            ((AlertDialog) dialog).getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);

        } else {
            // Something into edit text. Enable the button.
            ((AlertDialog) dialog).getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(true);
        }

    }
});

以下是经过编辑的历史记录,可以作为更多详细信息参考

这是一个示例代码,尝试一下

AlertDialog.Builder builder = new AlertDialog.Builder(AddSchedule.this);
builder.setIcon(android.R.drawable.ic_dialog_info);
builder.setTitle("Alert dialog title");
builder.setMessage("Dialog message");
builder.setPositiveButton("Button1", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface arg0, int arg1) {
        //DO TASK
    }
});
builder.setNegativeButton("Button2", new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface arg0, int arg1) {
        //DO TASK
    }
});

AlertDialog dialog = builder.create();
dialog.show();

// After calling show method, you need to check your condition and enable/disable the dialog buttons 
if (your_condition_true) {
    // BUTTON1 is the positive button
    dialog.getButton(AlertDialog.BUTTON1).setEnabled(false);
}

对于否定按钮

dialog.getButton(AlertDialog.BUTTON2).setEnabled(false); //BUTTON2 is negative button

对于按钮id参考 alert_dialog.xml

编辑:

setOnShowListener自8级API(升级Froyo),做同样的,

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setPositiveButton(android.R.string.ok, null);

AlertDialog dialog = builder.create();
dialog.setOnShowListener(new OnShowListener() {

    @Override
    public void onShow(DialogInterface dialog) {
        if (condition) {
            ((AlertDialog)dialog).getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);
        }
    }
});

dialog.show();

已编辑

new AlertDialog.Builder(this)
    .setMessage("This may take a while")
    .setPositiveButton("OK", new android.content.DialogInterface.OnClickListener() {

        @Override
        public void onClick(DialogInterface dialog, int which) {
            ((AlertDialog)dialog).getButton(which).setVisibility(View.INVISIBLE);
            // the rest of your stuff
        }

    }).show();


如果我错了,请纠正我,但是当您再次调用AlertDialog时,它再次调用了它的对象,还是仍然使用相同的对象。我不知道这种方法。请您简要说明一下?谢谢:)
NovusMobile

对于略读者,我想添加该dialog.getButton()仅适用于AlertDialogs,因此您可能需要在后续内容中将对话框强制转换为AlertDialog。
Noumenon

不起作用-我也阅读了至少5倍的代码,但仍然不知道为什么它应该起作用:)正确的答案来自尼克·帕尔默
6

@qkx您能解释一下您要做什么。可以显示相关代码吗?而且不要讽刺,不要投反对票。
Pankaj Kumar 2014年

1
我不想讽刺,粗鲁。我也尝试取消投票,但是这是不可能的...但是,再次出现问题-您的代码中哪里有文本侦听器,您能告诉我吗?如果只调用一次,则无所谓条件。如果您没有像下面的尼克这样的文本侦听器,那么您的解决方案根本不可能工作...或者我错过了一些东西。或发送给我一些简单的android项目以证明它是有效的;)
qkx 2014年

25

这些答案都不能真正解决问题。

我使用其中包含EditText和该视图上的TextWatcher的自定义布局来完成此操作。

final LinearLayout layout = (LinearLayout) inflator.inflate(R.layout.text_dialog, null);
final EditText text = (EditText) layout.findViewById(R.id.text_edit);
final AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setView(layout);
// Now add the buttons...
builder.setPositiveButton(R.string.ok, new AlertDialog.OnClickListener() {
    // Left out for brevity...
}
builder.setNegativeButton(R.string.cancel, new AlertDialog.OnClickListener() {
    // Left out for brevity...
}

// Create the dialog
final AlertDialog d = builder.create();

// Now add a TextWatcher that will handle enable/disable of save button
text.addTextChangedListener(new TextWatcher() {
    private void handleText() {
        // Grab the button
        final Button okButton = d.getButton(AlertDialog.BUTTON_POSITIVE);
        if(text.getText().length() == 0) {
            okButton.setEnabled(false);
        } else {
            okButton.setEnabled(true);
        }
    }
    @Override
    public void afterTextChanged(Editable arg0) {
        handleText();
    }
    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {
        // Nothing to do
    }
    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {
       // Nothing to do
    }
});

// show the dialog
d.show();
// and disable the button to start with
d.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);

这个答案是不完整的,没有声明d
androidguy

编辑添加d的构造。
尼克·帕尔默

4

这是启用和禁用对话框的肯定按钮的完整代码:

AlertDialog.Builder builder = new AlertDialog.Builder(this);
LayoutInflater layoutInflater = MainActivity.this.getLayoutInflater();
View view = layoutInflater.inflate(R.layout.dialog,null);

builder.setView(view);
builder.setTitle("Test");
builder.setPositiveButton("ok", new DialogInterface.OnClickListener() {
    @Override
    public void onClick(DialogInterface dialog, int which) {
        Toast.makeText(MainActivity.this, "Ok clicked", Toast.LENGTH_SHORT).show();
        dialog.dismiss();
    }
});
builder.setNegativeButton("cancel", null);

final AlertDialog alertDialog = builder.create();

alertDialog.show();

EditText editText = (EditText)view.findViewById(R.id.mobile_number);
alertDialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);
editText.addTextChangedListener(new TextWatcher() {
    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after) {}

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count) {}

    @Override
    public void afterTextChanged(Editable s) {
        if (s.length() >= 1) {
            alertDialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(true);
        } else {
            alertDialog.getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);

        }
    }
});

1

您可以将一个侦听器写入编辑文本框,然后尝试启用或禁用按钮。这是xamarin的示例代码。

var dialog = builder.Create();

dialog.Show();

var btnOk = dialog.GetButton((int)DialogButtonType.Positive).Enabled = false;

_enterTextDialogEditText.AfterTextChanged += (sender, e) => {
  if (!string.IsNullOrEmpty(_enterTextDialogEditText.Text)) {
    dialog.GetButton((int)DialogButtonType.Positive).Enabled = true;
  } else {
    dialog.GetButton((int)DialogButtonType.Positive).Enabled = false;
  }
};

0

对于使用视图持有者从数据库列表视图中删除记录,您在getview()方法中使用了此代码。

viewHolder.btn.setOnClickListener(new OnClickListener(){

                @Override
                public void onClick(View arg0) {
                    // TODO Auto-generated method stub
                    AlertDialog.Builder alertDialog2 = new AlertDialog.Builder(
                            Favorate.this.getParent());

                    // Setting Dialog Title
                    alertDialog2.setTitle("Confirm Delete...");

                    // Setting Dialog Message
                    alertDialog2
                            .setMessage("Are you sure you want delete ?");

                    // Setting Icon to Dialog
                    alertDialog2.setIcon(R.drawable.delete);

                    // Setting Positive "Yes" Btn
                    alertDialog2.setPositiveButton("YES",
                            new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog,
                                        int which) {
                                    // Write your code here to execute after
                                    // dialog

                                    int id = _items.get(position).id;
                                    db.deleterecord(id);

                                    db.close();
                                }
                            });
                    // Setting Negative "NO" Btn
                    alertDialog2.setNegativeButton("NO",
                            new DialogInterface.OnClickListener() {
                                public void onClick(DialogInterface dialog,
                                        int which) {
                                    // Write your code here to execute after
                                    // dialog

                                    dialog.cancel();
                                }
                            });

                    // Showing Alert Dialog
                    alertDialog2.show();

                }
            });

阅读更多


0

这个dialogFragment将为您完成这项工作。请注意,在屏幕旋转后,该对话框将保持打开状态,并保留用户已经键入的任何文本。如果您不希望这种情况发生,则需要在活动的onStop中消除该片段。可以将newInstance方法签名更改为所需的任何内容。

import android.app.Activity;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AlertDialog;
import android.text.Editable;
import android.text.TextWatcher;
import android.widget.EditText;

public class TextViewDialogFragment extends DialogFragment implements DialogInterface.OnClickListener, DialogInterface.OnShowListener, TextWatcher
{
    final static private String TITLE = "title", MESSAGE = "message", IDENTIFIER = "identifier", INPUT_TYPE = "inputType", POSITIVE_TEXT = "pText", NEGATIVE_TEXT = "nText", CANCELABLE = "cancelable";

    public TextViewDialogFragment()
    {
        super();
    }

    static public TextViewDialogFragment newInstance(int title, @Nullable String message, int identifier, int inputType, int positiveText, int negativeText, boolean cancelable)
    {
        TextViewDialogFragment fragement = new TextViewDialogFragment();
        Bundle args = new Bundle();
        args.putInt(TITLE, title);
        args.putString(MESSAGE, message);
        args.putInt(IDENTIFIER, identifier);
        args.putInt(INPUT_TYPE, inputType);
        args.putInt(POSITIVE_TEXT, positiveText);
        args.putInt(NEGATIVE_TEXT, negativeText);
        args.putBoolean(CANCELABLE, cancelable);
        fragement.setArguments(args);
        return fragement;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState)
    {
        Activity activity =  getActivity();
        Bundle args = getArguments();
        EditText input = new EditText(activity);
        input.setInputType(args.getInt(INPUT_TYPE));
        input.setId(R.id.dialog_edit_text);
        input.addTextChangedListener(this);
        AlertDialog.Builder alert = new AlertDialog.Builder(activity);
        alert.setCancelable(args.getBoolean(CANCELABLE)).setTitle(args.getInt(TITLE)).setMessage(args.getString(MESSAGE)).setView(input).setPositiveButton(args.getInt(POSITIVE_TEXT), this);
        int negativeText = args.getInt(NEGATIVE_TEXT);
        if (negativeText != 0)
        {
            alert.setNegativeButton(negativeText, this);
        }
        AlertDialog dialog = alert.create();
        dialog.setOnShowListener(this);
        return dialog;
    }

    @Override
    public void onShow(DialogInterface dialog)
    {
        // After device rotation there may be some text present.
        if (((EditText)((AlertDialog) dialog).findViewById(R.id.dialog_edit_text)).length() == 0)
        {
            ((AlertDialog) dialog).getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(false);
        }
    }

    @Override
    public void onClick(DialogInterface dialog, int which)
    {
        String text = ((EditText)((AlertDialog) dialog).findViewById(R.id.dialog_edit_text)).getText().toString();
        ((Callbacks) getActivity()).onTextViewDialogResult(which, getArguments().getInt(IDENTIFIER), text);
    }

    @Override
    public void onCancel(DialogInterface dialog)
    {
        ((Callbacks) getActivity()).onTextViewDialogActivityCancelled(getArguments().getInt(IDENTIFIER));
        super.onCancel(dialog);
    }

    @Override
    public void beforeTextChanged(CharSequence s, int start, int count, int after)
    {
    }

    @Override
    public void onTextChanged(CharSequence s, int start, int before, int count)
    {
    }

    @Override
    public void afterTextChanged(Editable s)
    {
        ((AlertDialog) getDialog()).getButton(AlertDialog.BUTTON_POSITIVE).setEnabled(s.length() > 0);
    }

    void setMessage(String message)
    {
        Bundle args = getArguments();
        args.putString(MESSAGE, message);
        setArguments(args);
    }

    interface Callbacks
    {
        void onTextViewDialogResult(int which, int identity, String text);
        void onTextViewDialogActivityCancelled(int identity);
    }
}

将工具添加到您的活动中(任何活动类型都可以):

public class Myctivity extends AppCompatActivity implements TextViewDialogFragment.Callbacks
{
...
}

像这样在您的活动中创建diaglogFragment:

final static int SOMETHING = 1;
myDF = TextViewDialogFragment.newInstance(R.string.my_title, "my message", SOMETHING, InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_FLAG_CAP_WORDS | InputType.TYPE_TEXT_FLAG_CAP_SENTENCES, /* Whatever is best for your user. */    R.string.yay, android.R.string.cancel, true);

按以下方式处理活动中的结果:

@Override
public void onTextViewDialogResult(int which, int identity, String text)
{
    if (which == AlertDialog.BUTTON_NEGATIVE)
    {
        // User did not want to do anything.
        return;
    }
    // text now holds the users answer.
    // Identity can be used if you use the same fragment for more than one type of question.
}
@Override
public void onTextViewDialogActivityCancelled(int identity)
{
    // This is invoked if you set cancelable to true and the user pressed the back button.
}

您需要创建资源标识符,以便将此资源添加到res / values下的某个位置

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <item name="dialog_edit_text" type="id"/>
</resources> 

-1
if(editTextEmailAddress.getText().toString().length()==0)
 {
 btnCancelCross.setEnabled(false);
}
else
{
 btnCancelCross.setEnabled(true);

}

这可能会帮助您,谢谢。


谢谢,但这不是我想要的。我可以通过使用自定义对话框来完成它,并使用按钮创建一个布局并启用禁用它们。我正在寻找的是有没有一种方法可以禁用或启用对话框的内置正负按钮?如果您查看我共享的代码,您将看到我想要的。但是再次感谢您的代码。
2011年

2
请发表一篇关于主题答案的综合文章(只需编辑您现有的答案,就不要继续发表其他答案)。
Tim Post
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