📅  最后修改于: 2020-09-29 02:18:18             🧑  作者: Mango
Android AlertDialog可用于通过“确定”和“取消”按钮显示对话框消息。它可用于打扰并询问用户有关他/她选择继续还是终止的信息。
Android AlertDialog由三个区域组成:标题,内容区域和操作按钮。
Android AlertDialog是Dialog类的子类。
让我们来看一个简单的android警报对话框示例。
您可以有多个组件,这里我们只有一个textview。
(可选)您可以将对话框消息和标题存储在strings.xml文件中。
AlertDialog
Welcome to Alert Dialog
Javatpoint Alert Dialog
让我们编写代码来创建和显示AlertDialog。
package example.javatpoint.com.alertdialog;
import android.content.DialogInterface;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.app.AlertDialog;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
Button closeButton;
AlertDialog.Builder builder;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
closeButton = (Button) findViewById(R.id.button);
builder = new AlertDialog.Builder(this);
closeButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
//Uncomment the below code to Set the message and title from the strings.xml file
builder.setMessage(R.string.dialog_message) .setTitle(R.string.dialog_title);
//Setting message manually and performing action on button click
builder.setMessage("Do you want to close this application ?")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
finish();
Toast.makeText(getApplicationContext(),"you choose yes action for alertbox",
Toast.LENGTH_SHORT).show();
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// Action for 'NO' Button
dialog.cancel();
Toast.makeText(getApplicationContext(),"you choose no action for alertbox",
Toast.LENGTH_SHORT).show();
}
});
//Creating dialog box
AlertDialog alert = builder.create();
//Setting the title manually
alert.setTitle("AlertDialogExample");
alert.show();
}
});
}
}