Android 在 Dialog 中覆盖 onKeyDown答案

【问题标题】：Android overriding onKeyDown within DialogAndroid 在 Dialog 中覆盖 onKeyDown
【发布时间】：2011-07-01 18:28:56
【问题描述】：

我有一个活动，它一打开就打开一个对话框：

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    mPath = new File(getIntent().getExtras().getString("START_PATH"));
    FTYPE = getIntent().getExtras().getString("FILTER");

    showDialog(DIALOG_LOAD_FILE);        

}

我试图做到这一点，因此当用户单击后退按钮（仍在对话框中）时，整个活动都将退出。我有以下内容：

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {

    if (keyCode == KeyEvent.KEYCODE_BACK) {

            Intent resultIntent = new Intent();
            resultIntent.putExtra("FILE_PATH", mPath.toString());
            setResult(Activity.RESULT_OK, resultIntent);
            finish();           
    }

   return true;
}

如果对话框不再存在，这很好用，但如果对话框仍然处于活动状态，则不会被调用。想法？

【问题讨论】：

标签： android android-activity dialog back-button

【解决方案1】：

试试这个

AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
                this);
        // set prompts.xml to alertdialog builder
        alertDialogBuilder.setView(promptsView);
        alertDialogBuilder
        .setCancelable(true);

        // create alert dialog
        final AlertDialog dialogDiscount = alertDialogBuilder.create();

        // show it
        dialogDiscount.show();

        OnKeyListener keylistener = new OnKeyListener() {

            @Override
            public boolean onKey(DialogInterface dialog, int keyCode, KeyEvent KEvent) {
                int keyaction = KEvent.getAction();

                if(keyaction == KeyEvent.ACTION_DOWN)
                {
                    int keycode = KEvent.getKeyCode();
                    int keyunicode = KEvent.getUnicodeChar(KEvent.getMetaState() );
                    char character = (char) keyunicode;
                    if(keycode==KeyCode.Enter){


                    }
                }
                return false;
            }
        };
        dialogDiscount.setOnKeyListener(keylistener );

【讨论】：

【解决方案2】：

您是否尝试在实例化Dialog 时覆盖Dialog 类中的onKeyDown()？我还没有测试过，但试试类似的东西

@Override
protected void onCreateDialog(int id) {
    Dialog dialog = null;
    switch(id) {
    case DIALOG_LOAD_FILE:
        dialog = new AlertDialog(mContext) {
            @Override
            public boolean onKeyDown(int keyCode, KeyEvent event) {
                if(keyCode == KeyEvent.KEYCODE_BACK) {
                    dismiss();
                    finish();
                    return true;
                }

                return super.onKeyDown(keyCode, event);
            }
        };   
        break;
    }
    return dialog;
}

【讨论】：

【解决方案3】：

您必须创建DialogInterface.OnKeyListener 的对象，并且可以覆盖onKey(DialogInterface dialog, int keyCode, KeyEvent event)。此方法捕获对话框内的关键事件。示例：

AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
//do something to your dialog like: dialogBuilder.setView(view);
DialogKeyListener dkl = new DialogKeyListener();        
dialogBuilder.setOnKeyListener(dkl);
AlertDialog dialog = dialogBuilder.create();
dialog.show();

和监听类：

private class DialogKeyListener implements android.content.DialogInterface.OnKeyListener
{
@Override
public boolean onKey(DialogInterface dialog, int keyCode, KeyEvent event) 
{
    if(keyCode == KeyEvent.KEYCODE_BACK)
    {
        dialog.dismiss();
        yourClassActivity.finish(); // or something like that
        return false;
    }
    return true
}
}

【讨论】：