如何在重新啟動，按回並更改方向后保留android app imageButton的onClick狀態

Question

我正在制作一個可以遠程控制燈泡的應用程序。 因此，我要求該應用自動保存以前的狀態（變量，onlick按鈕等），並在我重新啟動該應用后恢復它。 例如，如果我按下燈泡（在我的代碼中，它會在單擊時更改圖片）並且圖片也會更改，因此當我關閉應用程序並重新打開它時，顯示的圖像應該更改為一張。

這是我的代碼

package room.bt4u.com.roomcontrol;
import android.media.MediaPlayer;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ImageButton;
import android.widget.ImageSwitcher;
public class MainActivity extends AppCompatActivity {
ImageButton ib;
MediaPlayer toggleSound;
ImageButton aButton,aButton2;

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    toggleSound=MediaPlayer.create(this, R.raw.z);
    aButton = (ImageButton) findViewById(R.id.imageButton);
    aButton2 = (ImageButton) findViewById(R.id.imageButton2);
    SharedPreferences sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
    Boolean c = sharedPreferences.getBoolean("clicked", false);
    Boolean d = sharedPreferences.getBoolean("clicked2",false);

    if(c) {
        aButton.setImageResource(R.drawable.on);
    }
    else {
        aButton.setImageResource(R.drawable.off);

    }
    if(d){

        aButton2.setImageResource(R.drawable.on);
    }
    else {

        aButton2.setImageResource(R.drawable.off);
    }
    // ATTENTION: This was auto-generated to implement the App Indexing API.
    // See https://g.co/AppIndexing/AndroidStudio for more information.
    client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
}


public void buttonClick(View v) {
    SharedPreferences sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
    Boolean c = sharedPreferences.getBoolean("clicked",false);
    if (!c) {
        aButton.setImageResource(R.drawable.on);
        toggleSound.start();
        sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putBoolean("clicked", true);
        editor.commit();
    }
    if(c){
        aButton.setImageResource(R.drawable.off);
        sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor = sharedPreferences.edit();
        editor.putBoolean("clicked", false);
        editor.commit();
        toggleSound.start();

    }
}
public void buttonClick2(View v) {
    SharedPreferences sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
    Boolean d = sharedPreferences.getBoolean("clicked",false);
    if (!d) {
        aButton2.setImageResource(R.drawable.on);
        toggleSound.start();
        sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor.putBoolean("clicked2", true);
        editor.commit();
    }
    if(d){
        aButton2.setImageResource(R.drawable.off);
        sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
        SharedPreferences.Editor editor = sharedPreferences.edit();
        editor = sharedPreferences.edit();
        editor.putBoolean("clicked2", false);
        editor.commit();
        toggleSound.start();

    }
}

這是XML FILE

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="room.bt4u.com.roomcontrol.MainActivity"
android:orientation="vertical">

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="ROOM NO. 1046"
    android:textSize="45sp"
    android:textStyle="bold"
    android:layout_centerHorizontal="true"
    android:textColor="#0786e7"
    android:id="@+id/textView"
    android:includeFontPadding="false"
   android:gravity="center_horizontal"
    />


<ImageButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageButton"
    android:layout_below="@+id/textView"
    android:src="@drawable/off"
    android:layout_marginTop="35dp"
    android:layout_alignParentLeft="true"
    android:background="#01FFFFFF"
    android:onClick="buttonClick"/>

<ImageButton
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:id="@+id/imageButton2"
    android:layout_alignTop="@+id/imageButton"
    android:layout_below="@+id/textView"
    android:src="@drawable/off"
    android:layout_alignParentRight="true"
    android:layout_alignParentEnd="true"
    android:background="#01FFFFFF"
    android:onClick="buttonClick2"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:text="Swarnveer&apos;s"
    android:id="@+id/textView2"
    android:layout_below="@+id/imageButton"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginLeft="20dp"
    android:textStyle="bold"
    android:textColor="#f20606"/>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:text="Sajal&apos;s"
    android:id="@+id/textView3"

    android:layout_below="@+id/imageButton2"
    android:layout_alignRight="@+id/imageButton2"
    android:layout_alignEnd="@+id/imageButton2"
    android:layout_marginRight="35dp"
    android:layout_marginEnd="35dp"
    android:textStyle="bold"
    android:textColor="#f20606"/>

</RelativeLayout>

Answer 1

您可以使用SharedPreferences：

請參閱此處以獲取相關信息：您可以使用SharedPreferences在手機上保存少量設置數據。

在onPause() ，使用以下代碼：

SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);
prefs.edit().putString("myKey", "myColorState").apply();

這樣，“ myColorState”的設置將保存在鍵“ myKey”下。

在onResume()您可以使用

SharedPreferences prefs = this.getSharedPreferences("com.example.app", Context.MODE_PRIVATE);
String myColor = prefs.getString("myKey", "defaultValue"); 

這樣，您就可以擁有數據，並可以在活動中使用它們

Answer 2

如果您與燈泡之間沒有雙向通信，則將狀態保存到SharedPreferences似乎是最好的方法。

您可以在Activity或Fragment生命周期方法（ onConfigurationChanged() ， onResume() ， onStart() ）中從SharedPreferences中檢索數據。

在此處查看SharedPreferences

Answer 3

您可以使用SharedPref通過更改屏幕方向或按Backpress上的任何鍵來保存數據，也可以使用此鍵再次獲取該數據。

Answer 4

    Try this:


        @Override
        protected void onCreate(Bundle savedInstanceState) {

            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            toggleSound= MediaPlayer.create(this, R.raw.z);
            SharedPreferences sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
            Boolean c = sharedPreferences.getBoolean("clicked");
            if(c){
                aButton.setImageResource(R.drawable.on);
            }
            else {
                aButton.setImageResource(R.drawable.off);
            }        
        }


        public void buttonClick(View v) {
            switch (choose){
                case 1:ImageButton aButton = (ImageButton) v;
                    aButton.setImageResource(R.drawable.on);
                    toggleSound.start();
                    choose++;
                    SharedPreferences sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
                    SharedPreferences.Editor editor = sharedPreferences.edit();
                    editor.putBoolean("clicked", true);
                    editor.commit();
                    break;
                case 2:ImageButton bButton = (ImageButton) v;
                    bButton.setImageResource(R.drawable.off);
SharedPreferences sharedPreferences = getSharedPreferences("NAME", Context.MODE_PRIVATE);
                    SharedPreferences.Editor editor = sharedPreferences.edit();
                    editor.putBoolean("clicked", false);
                    editor.commit();
                    toggleSound.start();
                    choose--;
                    break;
            }