Android Imagebutton 更改 Image OnClick

Android Imagebutton change Image OnClick

提问by user1205415

I just added a new drawablefolder under resfolder. In the drawablefolder, i copied the ic_launcher.pngfile from drawable-hdpifolder. I wanna change the standard ImageButtonimage through the new one when i press the button. I wrote some code, but when i start the app, it crashes.

我刚刚drawable在res文件夹下添加了一个新文件夹。在drawable文件夹中，我ic_launcher.png从drawable-hdpi文件夹中复制了文件。ImageButton当我按下按钮时，我想通过新的图像更改标准图像。我写了一些代码，但是当我启动应用程序时，它崩溃了。

Button imgButton; 

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    findViewById(R.id.imgButton).setOnClickListener(imgButtonHandler);      
}

View.OnClickListener imgButtonHandler = new View.OnClickListener() {

    public void onClick(View v) {

        imgButton.setBackgroundResource(R.drawable.ic_launcher);

    }
};

EDIT: I changed to this, and this also not works.

编辑：我改为这个，这也不起作用。

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    imgButton = (Button) findViewById(R.id.imgButton);
    imgButton.setOnClickListener(imgButtonHandler);
}


View.OnClickListener imgButtonHandler = new View.OnClickListener() {

    public void onClick(View v) {
        imgButton.setBackgroundResource(R.drawable.ic_launcher);

    }
};

EDIT 2: THIS WORKS. Thanks to all.

编辑 2：这有效。谢谢大家。

ImageButton button;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    button= (ImageButton)findViewById(R.id.imgButton);
    button.setOnClickListener(imgButtonHandler);
}


View.OnClickListener imgButtonHandler = new View.OnClickListener() {

    public void onClick(View v) {
        button.setBackgroundResource(R.drawable.ic_launcher);

    }
};

回答by Yassine Souabni

This misled me a bit - it should be setImageResourceinstead of setBackgroundResource:) !!

这有点误导了我 - 它应该setImageResource而不是setBackgroundResource:) !!

The following works fine :

以下工作正常：

ImageButton btn = (ImageButton)findViewById(R.id.imageButton1);       
 btn.setImageResource(R.drawable.actions_record);

while when using the setBackgroundResourcethe actual imagebutton's image stays while the background image is changed which leads to a ugly looking imageButton object

而当使用setBackgroundResource实际的图像按钮的图像时，背景图像被改变，这导致一个难看的图像按钮对象

Thanks.

谢谢。

回答by mismanc

<ImageButton android:src="@drawable/image_btn_src" ... />

image_btn_src.xml

image_btn_src.xml

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true" android:drawable="@drawable/icon_pressed"/>
<item android:state_pressed="false" android:drawable="@drawable/icon_unpressed"/>
</selector>

回答by Carnal

That is because imgButton is null. Try this instead:

那是因为 imgButton 为空。试试这个：

findViewById(R.id.imgButton).setBackgroundResource(R.drawable.ic_action_search);

or much easier to read:

或更容易阅读：

imgButton = (Button) findViewById(R.id.imgButton);
imgButton.setOnClickListener(imgButtonHandler);

then in onClick: imgButton.setBackgroundResource(R.drawable.ic_action_search);

然后在onClick中： imgButton.setBackgroundResource(R.drawable.ic_action_search);

回答by John Smith

You can do it right in your XML file:

你可以在你的 XML 文件中做到这一点：

android:onClick="@drawable/ic_action_search"

回答by hsz

You have assing button to your imgButtonvariable:

你有你的imgButton变量assing 按钮：

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    imgButton = (Button) findViewById(R.id.imgButton);
    imgButton.setOnClickListener(imgButtonHandler);
}

回答by Oksana Kryvenko

To switch between different images when the ImageButton is clicked I used a boolean like this:

要在单击 ImageButton 时在不同图像之间切换，我使用了这样的布尔值：

ImageButton imageButton;
boolean buttonOn;

imageButton.setOnClickListener(new View.OnClickListener() {
     @Override
     public void onClick(View v) {
         if (!buttonOn) {
             buttonOn = true;
             imageButton.setBackground(getResources().getDrawable(R.drawable.button_is_on)); 
         } else {
             buttonOn = false;
             imageButton.setBackground(getResources().getDrawable(R.drawable.button_is_off));
         }
     }
});