警报对话框不适用

Question

当我按下按钮时，警报对话框在此处没有出现是代码：请您能告诉我它怎么了，我可以做什么解决它。

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.row_item);
    Button bDR = (Button) findViewById(R.id.bDR);
    bDR.setOnClickListener(new OnClickListener(){
        @Override
        public void onClick(View v) {
            AlertDialog.Builder builder = new AlertDialog.Builder(DeleteRenameList.this);
            builder.setCancelable(true);
            builder.setMessage("Would you like to delete or rename the list?");
            builder.setNegativeButton("Delete", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                }
            });
            builder.setNeutralButton("Rename", new DialogInterface.OnClickListener() {
                @Override
                public void onClick(DialogInterface dialog, int which) {

                }
            });
        AlertDialog alert = builder.create();
        alert.show();
}
    });

Plese帮助

Answer 1

尝试此

@Override
 protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.row_item);
Button bDR = (Button) findViewById(R.id.bDR);
bDR.setOnClickListener(new OnClickListener(){
    @Override
    public void onClick(View v) {
        AlertDialog.Builder builder = new 
         AlertDialog.Builder(DeleteRenameList.this).create();
        builder.setCancelable(true);
        builder.setMessage("Would you like to delete or rename the list?");
        builder.setNegativeButton("Delete", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {

            }
        });
        builder.setNeutralButton("Rename", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {

            }
        });
    AlertDialog.show();
    }
    });

Answer 2

尝试以下格式：

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
    Context context = this;
    Button button;
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        button = (Button) findViewById(R.id.buttonAlert);
        // add button listener
        button.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View arg0) {
            AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
                context);
            // set title
            alertDialogBuilder.setTitle("Your Title");
            // set dialog message
            alertDialogBuilder
                .setMessage("Would you like to delete or rename the list?")
                .setCancelable(false)
                .setPositiveButton("Delete",new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog,int id) {
                    }
                  })
                .setNegativeButton("Rename",new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog,int id) {
                    }
                });
                // create alert dialog
                AlertDialog alertDialog = alertDialogBuilder.create();
                // show it
                alertDialog.show();
            }
        });
    }
}

源