Java 在Android中使用KeyEvent.KEYCODE_表示怀疑_Java_Android_Keyevent_Keycode_Onkeyup

Java 在Android中使用KeyEvent.KEYCODE_表示怀疑

java android

Java 在Android中使用KeyEvent.KEYCODE_表示怀疑,java,android,keyevent,keycode,onkeyup,Java,Android,Keyevent,Keycode,Onkeyup,我有三项活动。第一个活动有一个“向右”图像按钮。（移动到第二个活动）第二个活动同时具有“向右”和“向左”图像按钮。（返回到第一个活动或移动到第三个活动）。第三项活动有一个“向左”按钮，可移动到第二项活动。我已经为后退键创建了事件问题是，您从第一个导航到第三个，然后返回并导航到第三个活动。第一个活动---点击向右----第二个活动---点击向右----第三个活动---点击向左----第二个活动----点击向左----第一个活动----点击向右----第二个活动---点击向右----第三

我有三项活动。第一个活动有一个“向右”图像按钮。（移动到第二个活动）第二个活动同时具有“向右”和“向左”图像按钮。（返回到第一个活动或移动到第三个活动）。第三项活动有一个“向左”按钮，可移动到第二项活动。我已经为后退键创建了事件

问题是，您从第一个导航到第三个，然后返回并导航到第三个活动。第一个活动---点击向右----第二个活动---点击向右----第三个活动---点击向左----第二个活动----点击向左----第一个活动----点击向右----第二个活动---点击向右----第三个活动

现在，如果我在第三个活动中按back键，它将移动到第二个。按下这里的“后退”键，它将移动到第一位。但在这里，如果我按下后退键，它会再次进入第一个活动。只有在第一个活动中按第二个后退键才能退出应用程序。另外一个问题是，如何使Imagebutton仅在按下时可见

我说得通吗

FirstActivity.java

package com.stylingandroid.Animation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class FirstActivity extends Activity
{
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.first );
        ((ImageButton)findViewById( R.id.NextButton )).setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                startActivity( new Intent( FirstActivity.this, SecondActivity.class ) );
                overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
            }
        });
    }
    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            finish();
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }

    public boolean onCreateOptionsMenu(Menu menu) {
          MenuInflater inflater = getMenuInflater();
          inflater.inflate(R.menu.options_menu, menu);
          return true;
        }

    public boolean onOptionsItemSelected(MenuItem item) 
    {
          switch (item.getItemId()) 
          {
          case R.id.next:
              startActivity( new Intent( FirstActivity.this, SecondActivity.class ) );
              overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
              return true;

          case R.id.exit:
                finish();

          default:
                return super.onOptionsItemSelected(item);
          }
    }

}

package com.stylingandroid.Animation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class SecondActivity extends Activity
{
    private ImageButton nextbutton;
    private ImageButton backbutton;
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.second );
        nextbutton = (ImageButton) findViewById(R.id.NextButton);
        backbutton = (ImageButton) findViewById(R.id.BackButton);
        nextbutton.setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                startActivity( new Intent( SecondActivity.this, ThirdActivity.class ) );
                overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
            }
        });
        backbutton.setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                finish();
                startActivity( new Intent( SecondActivity.this, FirstActivity.class ) );
                overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
            }
        });
    }

    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            finish();
            overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }
}

package com.stylingandroid.Animation;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageButton;

public class ThirdActivity extends Activity
{
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.third );
        ((ImageButton)findViewById( R.id.BackButton )).setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                goBack();
            }
        });
    }

    private void goBack()
    {
        finish();
        overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
    }

    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            goBack();
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }
}

SecondActivity.java

package com.stylingandroid.Animation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class FirstActivity extends Activity
{
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.first );
        ((ImageButton)findViewById( R.id.NextButton )).setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                startActivity( new Intent( FirstActivity.this, SecondActivity.class ) );
                overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
            }
        });
    }
    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            finish();
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }

    public boolean onCreateOptionsMenu(Menu menu) {
          MenuInflater inflater = getMenuInflater();
          inflater.inflate(R.menu.options_menu, menu);
          return true;
        }

    public boolean onOptionsItemSelected(MenuItem item) 
    {
          switch (item.getItemId()) 
          {
          case R.id.next:
              startActivity( new Intent( FirstActivity.this, SecondActivity.class ) );
              overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
              return true;

          case R.id.exit:
                finish();

          default:
                return super.onOptionsItemSelected(item);
          }
    }

}

package com.stylingandroid.Animation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class SecondActivity extends Activity
{
    private ImageButton nextbutton;
    private ImageButton backbutton;
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.second );
        nextbutton = (ImageButton) findViewById(R.id.NextButton);
        backbutton = (ImageButton) findViewById(R.id.BackButton);
        nextbutton.setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                startActivity( new Intent( SecondActivity.this, ThirdActivity.class ) );
                overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
            }
        });
        backbutton.setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                finish();
                startActivity( new Intent( SecondActivity.this, FirstActivity.class ) );
                overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
            }
        });
    }

    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            finish();
            overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }
}

package com.stylingandroid.Animation;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageButton;

public class ThirdActivity extends Activity
{
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.third );
        ((ImageButton)findViewById( R.id.BackButton )).setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                goBack();
            }
        });
    }

    private void goBack()
    {
        finish();
        overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
    }

    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            goBack();
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }
}

ThirdActivity.java

package com.stylingandroid.Animation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

import android.view.KeyEvent;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class FirstActivity extends Activity
{
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.first );
        ((ImageButton)findViewById( R.id.NextButton )).setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                startActivity( new Intent( FirstActivity.this, SecondActivity.class ) );
                overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
            }
        });
    }
    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            finish();
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }

    public boolean onCreateOptionsMenu(Menu menu) {
          MenuInflater inflater = getMenuInflater();
          inflater.inflate(R.menu.options_menu, menu);
          return true;
        }

    public boolean onOptionsItemSelected(MenuItem item) 
    {
          switch (item.getItemId()) 
          {
          case R.id.next:
              startActivity( new Intent( FirstActivity.this, SecondActivity.class ) );
              overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
              return true;

          case R.id.exit:
                finish();

          default:
                return super.onOptionsItemSelected(item);
          }
    }

}

package com.stylingandroid.Animation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;

public class SecondActivity extends Activity
{
    private ImageButton nextbutton;
    private ImageButton backbutton;
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.second );
        nextbutton = (ImageButton) findViewById(R.id.NextButton);
        backbutton = (ImageButton) findViewById(R.id.BackButton);
        nextbutton.setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                startActivity( new Intent( SecondActivity.this, ThirdActivity.class ) );
                overridePendingTransition( R.anim.slide_in_left, R.anim.slide_out_left );
            }
        });
        backbutton.setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                finish();
                startActivity( new Intent( SecondActivity.this, FirstActivity.class ) );
                overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
            }
        });
    }

    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            finish();
            overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }
}

package com.stylingandroid.Animation;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageButton;

public class ThirdActivity extends Activity
{
    @Override
    protected void onCreate( Bundle savedInstanceState )
    {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.third );
        ((ImageButton)findViewById( R.id.BackButton )).setOnClickListener( new OnClickListener()
        {
            @Override
            public void onClick( View v )
            {
                goBack();
            }
        });
    }

    private void goBack()
    {
        finish();
        overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
    }

    @Override
    public boolean onKeyUp( int keyCode, KeyEvent event )
    {
        if( keyCode == KeyEvent.KEYCODE_BACK )
        {
            goBack();
            return true;
        }
        return super.onKeyUp( keyCode, event );
    }
}

这里有一个bug：

    backbutton.setOnClickListener( new OnClickListener()
    {
        @Override
        public void onClick( View v )
        {
            finish();
            startActivity( new Intent( SecondActivity.this, FirstActivity.class ) );
            overridePendingTransition( R.anim.slide_in_right, R.anim.slide_out_right );
        }
    });

您正在

finish（）
另一方面，你想在这里实现什么
@Override
public boolean onKeyUp( int keyCode, KeyEvent event )
{
    if( keyCode == KeyEvent.KEYCODE_BACK )
    {
        goBack();
        return true;
    }
    return super.onKeyUp( keyCode, event );
}

系统将后退按钮连接到finish（）
。您不需要在onKey级别处理它。
除了不同的布局外，每个活动都是相同的吗？您是否考虑过使用新兼容性库中的ViewPager？啊!！他们是一样的！我只是在尝试一些动画！我不知道viewpager。我要试试看！谢谢如果我注释掉finish（），第二个活动会弹出，即使我在第一个活动中。我知道系统会将back按钮附加到finish（）。但这一转变并不顺利。为了使动画平滑，我使用了goBack（）；不要注释掉完成，而是注释掉开始活动