Android添加点击事件秒退

package com.example.test;

import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;

import com.google.android.material.bottomnavigation.BottomNavigationView;

import androidx.appcompat.app.AppCompatActivity;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;

public class MainActivity extends AppCompatActivity {

    private ImageButton Ib_1;
    private ImageButton Ib_2;
    private ImageButton Ib_3;
    private ImageButton Ib_4;
    private ImageButton Ib_5;
    private ImageButton Ib_6;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        getSupportActionBar().hide();
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        BottomNavigationView navView = findViewById(R.id.nav_view);
        // Passing each menu ID as a set of Ids because each
        // menu should be considered as top level destinations.
        AppBarConfiguration appBarConfiguration = new AppBarConfiguration.Builder(
                R.id.navigation_home, R.id.navigation_dashboard, R.id.navigation_notifications)
                .build();
        NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
        NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);
        NavigationUI.setupWithNavController(navView, navController);
        Ib_1=(ImageButton) findViewById(R.id.imageButton);
        Ib_1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                System.out.println("Hello");
            }
        });
    }
        }




其实就是想给ImageBox加一个点击事件,不知道为什么无法启动,是我写的有问题吗,请大神指教。

你好,初步看来可能是你隐藏actionbar代码的添加的位置错误导致的运行报错,详细的可以通过过滤Runtime查看编译报错的具体位置。

你当前将getSupportActionBar().hide() 写在setContentView(R.layout.activity_main);前面,写个是有问题的,如果需要隐藏actionbar可以参照一下方法。
方法一:
在onCreate方法中添加一句代码

将AppCompatActivity改为Activity,此时 requestWindowFeature(Window.FEATURE_NO_TITLE);是有效的 在AppCompatActivity下无效

requestWindowFeature(Window.FEATURE_NO_TITLE);

这句代码一定要添加到setContentView(R.layout.activity_main); 之前;
否则会报错(Caused by: android.util.AndroidRuntimeException: requestFeature() must be called before adding content);
方法二:

public class MainActivity extends Activity {
    ActionBar  actionBar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
 
        setContentView(R.layout.activity_main);
        actionBar=getSupportActionBar().hide();
    }
}

方法三:

还可以通过通过添加代码的方式更改主题;
在配置文件中通过android:theme=”“属性隐藏:

<activity
     android:name=".MainActivity"
     android:label="@string/app_name"
     <!-- 这行代码便可以隐藏ActionBar -->
     android:theme="@android:style/Theme.Light.NoTitleBar" >
     <intent-filter>
        <action android:name="android.intent.action.MAIN" />
 
        <category android:name="android.intent.category.LAUNCHER" />
     </intent-filter>
</activity>