定义使imageView可见和不可见的keyPreference

Question

我有三个活动，每个都有一个按钮。Act1与btn1，Act2与btn2，Act3与btn3。我有另一个活动作为主活动，有三个图像视图：ImageView1、imageView2和imageView3，所有这些最初都是不可见的。我希望这样，当我在act1中单击btn1时，MainActivity中的imageView1将可见，而当再次单击btn1，ImageView 1将再次不可见。与imageView2和imageView3类似，到目前为止，我有以下代码：

Activity1

public class Activity1 extends AppCompatActivity{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity1);

Button btn1 = (Button) findViewById(R.id.btn1);
btn1.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        String visibilityStr = PublicSharedPreferences.getDefaults("keyVisibility1", getApplicationContext());

        if (visibilityStr != null) {
            if (visibilityStr.equals("0")) {
                Toast.makeText(act1.this, "it visibled", Toast.LENGTH_SHORT).show();
                visibilityStr = "1";
btn1.setImageResource(R.mipmap.img1);

            } else {
                visibilityStr = "0";
                Toast.makeText(act1.this, "it invisibled", Toast.LENGTH_SHORT).show();
btn1.setImageResource(R.mipmap.img2);

            }
        } else {
            visibilityStr = "1";
            Toast.makeText(act1.this, "it visibled", Toast.LENGTH_SHORT).show();
btn1.setImageResource(R.mipmap.img1);

        }

        PublicSharedPreferences.setDefaults("keyVisibility1", visibilityStr, getApplicationContext());

    }
});
}





Activity2

public class Activity2 extends AppCompatActivity{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity2);


Button btn1 = (Button) findViewById(R.id.btn2);
btn1.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        String visibilityStr = PublicSharedPreferences.getDefaults("keyVisibility2", getApplicationContext());

        if (visibilityStr != null) {
            if (visibilityStr.equals("0")) {
                Toast.makeText(act2.this, "it visibled", Toast.LENGTH_SHORT).show();
btn2.setImageResource(R.mipmap.img1);

                visibilityStr = "1";
            } else {
                visibilityStr = "0";
                Toast.makeText(act2.this, "it invisibled", Toast.LENGTH_SHORT).show();
btn2.setImageResource(R.mipmap.img2);

            }
        } else {
            visibilityStr = "1";
            Toast.makeText(act2.this, "it visibled", Toast.LENGTH_SHORT).show();
btn2.setImageResource(R.mipmap.img1);

        }

        PublicSharedPreferences.setDefaults("keyVisibility2", visibilityStr, getApplicationContext());

    }
});
}



Activity3

public class Activity3 extends AppCompatActivity{

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity3);

Button btn1 = (Button) findViewById(R.id.btn3);
btn1.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View view) {
        String visibilityStr = PublicSharedPreferences.getDefaults("keyVisibility3", getApplicationContext());

        if (visibilityStr != null) {
            if (visibilityStr.equals("0")) {
                Toast.makeText(act3.this, "it visibled", Toast.LENGTH_SHORT).show();
Btn3.setImageResource(R.mipmap.img1);

                visibilityStr = "1";
            } else {
                visibilityStr = "0";
                Toast.makeText(act3.this, "it invisibled", Toast.LENGTH_SHORT).show();
btn3.setImageResource(R.mipmap.img2);

            }
        } else {
            visibilityStr = "1";
            Toast.makeText(act3.this, "it visibled", Toast.LENGTH_SHORT).show();
btn3.setImageResource(R.mipmap.img1);

        }

        PublicSharedPreferences.setDefaults("keyVisibility3", visibilityStr, getApplicationContext());
    }
});
}

主要活动与三个图像视图：

        ImageView imgView1 = (ImageView) findViewById(R.id.imgView1);
String visibilityStr= PublicSharedPreferences.getDefaults("keyVisibility1", getApplicationContext());

if (visibilityStr.equals("0"))
    imgView1.setVisibility(View.INVISIBLE);
else
    imgView1.setVisibility(View.VISIBLE);


ImageView imgView2 = (ImageView) findViewById(R.id.imgView2);
String visibilityStr= PublicSharedPreferences.getDefaults("keyVisibility2", getApplicationContext());

if (visibilityStr.equals("0"))
    imgView2.setVisibility(View.INVISIBLE);
else
    imgView2.setVisibility(View.VISIBLE);



ImageView imgView3 = (ImageView) findViewById(R.id.imgView3);
String visibilityStr= PublicSharedPreferences.getDefaults("keyVisibility3", getApplicationContext());

if (visibilityStr.equals("0"))
    imgView3.setVisibility(View.INVISIBLE);
else
    imgView3.setVisibility(View.VISIBLE);

和SharedPreferences类:

 public class PublicSharedPreferences {



    public static void setDefaults(String key, String value, Context context) {
        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
        SharedPreferences.Editor editor = prefs.edit();
        editor.putString(key, value);
        editor.commit();
    }

    public static String getDefaults(String key, Context context) {
        SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
        return preferences.getString(key, null);
    }


}

它们工作得很好。但问题是当我单击btn1时，Mainactive中的所有ImageViews都会发生变化（变得可见或不可见），或者当我单击btn3时，所有ImageViews都会发生变化。我想要btn1只改变ImageView1，btn2只改变ImageView2，btn3只改变ImageView3，而不是其中一个按钮改变所有的ImageView。我认为问题是我为所有人定义了一个键首选项。但我不知道如何为每个人定义特殊键。我该怎么做？请更改代码并再次编写它们。tnx。

Answer 1

让三个静态变量在单独的类名中保持不变。并用false初始化它们

public class Constant() {
    public static Boolean firstButton = false;
    public static Boolean secondButton = false;
    public static Boolean thirdButton = false;
}

现在，当您单击活动1的btn1时，请执行以下操作

btn1.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Constant.firstButton = !Constant.firstButton;
                // start new Activity
            }
        });

现在在您的其他活动中。在您的onCreatemetode中，只需这样做

imageView1.setVisibility(Constant.firstButton ? View.Visible: View.Gone);

Answer 2

您使用 1 个变量作为所有 3 个 if！

为每个活动/图像视图设置不同的变量

      ImageView imgView1 = (ImageView) findViewById(R.id.imgView1);
//keyVisibility1
String visibilityStr= PublicSharedPreferences.getDefaults("keyVisibility1", getApplicationContext());

if (visibilityStr.equals("0"))
    imgView1.setVisibility(View.INVISIBLE);
else
    imgView1.setVisibility(View.VISIBLE);


ImageView imgView2 = (ImageView) findViewById(R.id.imgView2);
//keyVisibility2
 visibilityStr= PublicSharedPreferences.getDefaults("keyVisibility2", getApplicationContext());

if (visibilityStr.equals("0"))
    imgView2.setVisibility(View.INVISIBLE);
else
    imgView2.setVisibility(View.VISIBLE);



ImageView imgView3 = (ImageView) findViewById(R.id.imgView3);
//keyVisibility3
 visibilityStr= PublicSharedPreferences.getDefaults("keyVisibility3", getApplicationContext());

if (visibilityStr.equals("0"))
    imgView3.setVisibility(View.INVISIBLE);
else
    imgView3.setVisibility(View.VISIBLE);