保存和恢復視圖狀態android

Question

我知道活動狀態保存和恢復。 但我想要做的是保存和恢復視圖的狀態。 我有一個自定義視圖和兩個overrided方法是：

@Override 
protected void onRestoreInstanceState(Parcelable state) { 
    if (state instanceof Bundle) { 
     Bundle bundle = (Bundle) state; 
     currentLeftX = bundle.getInt(CURRENT_LEFT_X_PARAM, 0); 
     currentTopY = bundle.getInt(CURRENT_TOP_Y_PARAM, 0); 
    } 
    super.onRestoreInstanceState(state); 
} 

@Override 
protected Parcelable onSaveInstanceState() { 
    super.onSaveInstanceState(); 
    Bundle bundle = new Bundle(); 
    bundle.putInt(CURRENT_LEFT_X_PARAM, currentLeftX); 
    bundle.putInt(CURRENT_TOP_Y_PARAM, currentTopY); 
    return bundle; 
} 

我預計這個工作無縫的，但遇到和錯誤：

Caused by: java.lang.IllegalArgumentException: Wrong state class, expecting View State but received class android.os.Bundle instead. This usually happens when two views of different type have the same id in the same hierarchy. This view's id is id/mapViewId. Make sure other views do not use the same id. at android.view.View.onRestoreInstanceState(View.java:6161)

但這種觀點在我的活動唯一的一個。所以，我問：

什麼是正確的方式來保存視圖的狀態？

Answer 1

看看這個答案：

How to prevent custom views from losing state across screen orientation changes

Answer 2

我可能是錯的，但我認爲你需要保存包父回報：

@Override 
protected Parcelable onSaveInstanceState() { 
    Parcelable bundle = super.onSaveInstanceState(); 
    bundle.putInt(CURRENT_LEFT_X_PARAM, currentLeftX); 
    bundle.putInt(CURRENT_TOP_Y_PARAM, currentTopY); 
    return bundle; 
} 

否則你失去超類保存的所有東西。

Answer 3

您放棄super.OnSaveInstanceState()的結果並返回自己的結果。 然後在OnRestoreInstanceState(Parcelable)您返回您創建的那個。

該解決方案是在這裏：

How to prevent custom views from losing state across screen orientation changes #2