Question

好的，我有一个有很多图像按钮的应用程序，我目前工作的是所有onClick个侦听器，当用户点击图像时图像会发生变化。我阅读并研究了可以使用onSavedInstance()和onRestore()保存这些图像按钮的状态。这就是我现在所拥有的，我只是为一个图像按钮尝试这个，因为如果这不正确我不想改变所有。

我也有按钮让我完成每个活动，问题是当我移动到另一个活动然后向后移动图像按钮更改不保存，如果从未按下按钮图像则返回。

我有一种感觉，我错过了一些非常简单的东西，因为我有观看和阅读一些教程，但仍然无法让它工作。如果可以帮助我理解我会很感激。

好的问题解决了我只在我的一个图像按钮上尝试使用共享首选项并将其放入暂停和恢复中。我现在可以按下按钮转动屏幕并退出应用程序而不会丢失数据。

public boolean isPressed;
private boolean isCandyPressed = false;
private static final String CANDY_PRESSED = "CandyPressed";
private SharedPreferences prefs;
private String PrefName = "MyPref";


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_desserts);


    vegetablesButton = (ImageButton) findViewById(R.id.vegetabesButton);


    candy = (ImageButton) findViewById(R.id.candy);
    chocolate = (ImageButton) findViewById(R.id.chocolate);
    cookies = (ImageButton) findViewById(R.id.cookies);
    cupcakes = (ImageButton) findViewById(R.id.cupcakes);
    doughnuts = (ImageButton) findViewById(R.id.doughnuts);
    iceCream = (ImageButton) findViewById(R.id.icecream);
    jello = (ImageButton) findViewById(R.id.jello);
    marshMellows = (ImageButton) findViewById(R.id.marshmellows);
    muffins = (ImageButton) findViewById(R.id.muffins);
    pudding = (ImageButton) findViewById(R.id.pudding);
    yogurt = (ImageButton) findViewById(R.id.yogurt);
    vegetablesButton = (ImageButton) findViewById(R.id.vegetabesButton);


    ImageChanger(chocolate, R.drawable.buttongrabchocolate, R.drawable.chocolate);
    ImageChanger(cookies, R.drawable.buttongrabcookies, R.drawable.cookies);
    ImageChanger(cupcakes, R.drawable.buttongrabcupcakes, R.drawable.cupcake);
    ImageChanger(doughnuts, R.drawable.buttongrabdoughnuts, R.drawable.doughnut);
    ImageChanger(iceCream, R.drawable.buttongrabicecream, R.drawable.icecream);
    ImageChanger(jello, R.drawable.buttongrabjello, R.drawable.jelly);
    ImageChanger(marshMellows, R.drawable.buttongrabmarshmellows, R.drawable.marshmellows);
    ImageChanger(muffins, R.drawable.buttongrabmuffins, R.drawable.muffin);
    ImageChanger(pudding, R.drawable.buttongrabpudding, R.drawable.pudding);
    ImageChanger(yogurt, R.drawable.buttongrabyogurt, R.drawable.yogurt);


    setCandyImage();
    candy.setOnClickListener(new View.OnClickListener() {

        public void onClick(View v) {
            if (!isCandyPressed) {
                candy.setBackgroundResource(R.drawable.buttongrabcandy);
                isCandyPressed = true;
            } else {
                candy.setBackgroundResource(R.drawable.candy);
                isCandyPressed = false;

            }
        }
    });
    vegetablesButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent myIntent = new Intent(Desserts.this, Items.class
            );
            Desserts.this.startActivity(myIntent);
        }
    });

}


protected void setCandyImage() {
    if (isCandyPressed) {
        candy.setBackgroundResource(R.drawable.buttongrabcandy);


    } else {
        candy.setBackgroundResource(R.drawable.candy);
    }
}

void ImageChanger(final ImageButton a, final int b, final int c) {
    a.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            if (isPressed) {
                a.setBackgroundResource(b);

            } else
                a.setBackgroundResource(c);
            isPressed = !isPressed;


        }
    });
}

@Override
protected void onPause() {
    super.onPause();
    prefs=getSharedPreferences(PrefName,MODE_PRIVATE);
    SharedPreferences.Editor editor=prefs.edit();

    editor.putBoolean(CANDY_PRESSED,isCandyPressed);
    editor.commit();
}

@Override
protected void onResume() {
    super.onResume();
    prefs=getSharedPreferences(PrefName,MODE_PRIVATE);
    isCandyPressed=prefs.getBoolean(CANDY_PRESSED,false);
    setCandyImage();

}

}

Answer 1

在活动中移动时不会保留按钮的状态，因为每次都会重新实例化活动对象，因此为了修复它，您只需将其设为static变量。

private static boolean isCandyPressed = false;

希望这能解决您的问题

保存图像按钮的状态

1 个答案: