Question

请帮忙我想为同一个按钮放几个执行命令我的意思是当我第一次按下按钮做某件事当第二次按下时再做一次，依此类推十次压力我尝试了这段代码，但它无法正常工作

function UseMapFunction(str) {
     var strArr = str.toLowerCase().split(' ');
     
     var newStrArr = strArr.map(function(val){
      return val.replace(val.charAt(0),val.charAt(0).toUpperCase());
     });
     console.log(newStrArr.join(' '));
}
UseMapFunction("one way to do it is with map");

function UseSubstring(str) {
     var strArr = str.split(' ');
     var newArr =[];
     for (var i = 0; i<strArr.length; i++){
       newArr.push(strArr[i].substring(0,1).toUpperCase() + strArr[i].substring(1,strArr[i].length).toLowerCase());
     }
  console.log(newArr.join(' '));
}
UseSubstring("alternatively use substring and it works fine too");

他总是做第一个条件而忽略了第二个条件我在Stack OverFlow网站上阅读了这段代码

public class ChickenBlanche extends AppCompatActivity
    implements NavigationView.OnNavigationItemSelectedListener {
Button b1;
int i=0;


b1=(Button) findViewById(R.id.btns);

    b1.setOnClickListener( new View.OnClickListener() {
        @SuppressLint("WrongConstant")
        @Override
        public void onClick(View view) {

            if(i == 0)
            {
                Intent in = new Intent();
                in.putExtra( REG_INT_TAG, quantity1);
                setResult(RESULT_OK,in);
                finish();

            }
            else if(i==1)
            {
                Intent in = new Intent();
                in.putExtra( REG_INT_TAG1, quantity1);
                setResult(RESULT_OK,in);
                finish();
            }
        }
    } );

但我真的不知道如何将它应用到我的按钮

Answer 1

尝试以下示例：

1）Demo4.class：------------

public class Demo4 extends AppCompatActivity {

private Button b;
public static final String WHICH = "which";
private SharedPreferences p;
public static final String REG_INT_TAG = "reg_int_tag";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_2);

    p = getApplicationContext().getSharedPreferences("p_key",
            0);

    b = (Button) findViewById(R.id.b);
    b.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            if (p != null) {
                switch (p.getInt(WHICH, 0)) {
                    case 0:
                        result("A");
                        break;
                    case 1:
                        result("B");
                        break;
                    case 2:
                        result("C");
                        break;
                    case 3:
                        result("D");
                        break;
                    case 4:
                        result("E");
                        break;
                    case 5:
                        result("F");
                        break;
                    case 6:
                        result("G");
                        break;
                    case 7:
                        result("H");
                        break;
                    case 8:
                        result("I");
                        break;
                    case 9:
                        result("J");
                        break;
                    default:
                        result("A");
                        break;
                }
            }
        }
    });
}

private void result(String value){

    Intent in = new Intent();
    in.putExtra(REG_INT_TAG,value);
    setResult(RESULT_OK,in);
    finish();
}

}

2）mainActivity.class：-------

public class mainActivity extends AppCompatActivity {

    private Button b2;
    private SharedPreferences p;
    private final int ACTIVITY_2 = 12345;

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

        p = getApplicationContext().getSharedPreferences("p_key",
                0);

        b2 = (Button) findViewById(R.id.b2);
        b2.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent i = new Intent(mainActivity.this , Demo4.class);
                startActivityForResult(i , ACTIVITY_2);
            }
        });
    }

    public void setInt(String Name, int value){
        if(p != null){
            SharedPreferences.Editor editor = p.edit();
            editor.putInt(Name, value);
            editor.apply();
        }
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if(requestCode == ACTIVITY_2){
            if(resultCode == RESULT_OK){
                if(data != null){
                    Toast.makeText(getApplicationContext() , data.getStringExtra(Demo4.REG_INT_TAG) , Toast.LENGTH_LONG).show();
                    updateWhich();
                }
            }
        }
    }


private void updateWhich(){

    if(p != null){
        int which = p.getInt(Demo4.WHICH , 0);
        setInt(Demo4.WHICH, (which >= 0 && which < 9) ? which + 1 : 0);
        // if which is between 0 including and 9 excluding increment which otherwise which = 0.
    }
}

}

3）activity_2.xml：--------

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
android:layout_height="match_parent">

<Button
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="Click"
    android:id="@+id/b"/>

</android.support.constraint.ConstraintLayout>

4）activity_main.xml：--------

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent"
android:layout_height="match_parent">

<Button
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="open 2"
    android:id="@+id/b2"/>

</android.support.constraint.ConstraintLayout>

Answer 2

按下按钮时每次增加i值。看看代码

b1=(Button) findViewById(R.id.btns);

b1.setOnClickListener( new View.OnClickListener() {
    @SuppressLint("WrongConstant")
    @Override
    public void onClick(View view) {

        if(i == 0)
        {
            Intent in = new Intent();
            in.putExtra( REG_INT_TAG, quantity1);
            setResult(RESULT_OK,in);
            finish();

        }
        else if(i==1)
        {
            Intent in = new Intent();
            in.putExtra( REG_INT_TAG1, quantity1);
            setResult(RESULT_OK,in);
            finish();
        }

        i=i+1;//increment i value on button click at every time.

         if(i=>maxValue){//If i value reach maximum point then should reset also
              i=0;
             }      
    }
} );

如何在同一按钮上切换执行指令？

2 个答案: