Question

我在一个页面上有2个图像，我想用下一个和上一个按钮改变它3次（1-2个图像）然后（3-4个图像）然后（5-6个图像）然后我点击在上一个按钮然后它显示（3-4图像）然后（1-2图像）。当我完成循环然后单击下一个或上一个按钮时，我的代码只工作一次然后没有任何反应，如果你在我的代码中发现任何错误然后纠正我，这是我的java代码：

 public class AlifPics extends Activity  {  

    TextView text1;
    TextView text2;
    TextView text3;
    TextView text4;
    TextView text5;  
    TextView text6;   
    TextView text7;
    ImageView img1;
    ImageButton imgBut1;
    ImageButton imgBut2; 
    ImageButton nextBtn;        
    ImageButton preBtn;
protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.alif_pics);
  text1 = (TextView) findViewById(R.id.textView1);
  text2 = (TextView) findViewById(R.id.textView2);
  text3 = (TextView) findViewById(R.id.textView3);
  text4 = (TextView) findViewById(R.id.textView4);
  text5 = (TextView) findViewById(R.id.textView5); 
  text6 = (TextView) findViewById(R.id.textView6);  
  text7 = (TextView) findViewById(R.id.textView7);
 img1 = (ImageView) findViewById(R.id.imageView1);
 imgBut1 = (ImageButton) findViewById(R.id.imageButton1);
 imgBut2 = (ImageButton) findViewById(R.id.imageButton2);
 nextBtn = (ImageButton) findViewById(R.id.next);
 preBtn = (ImageButton) findViewById(R.id.previous);         
                  }   
      // this Menu Button method goes to MainActivity
           public void indexHuroof(View v) {
         Intent i = new Intent(this, MainActivity.class);
        startActivity(i);
          }

 int counter = 1;
  String[] textvalue1 = { "a2", "a3" };
  String[] textvalue2 = { "b2", "b3" };
  String[] textvalue3 = { "c2", "c3" };
  String[] textvalue4 = { "d2", "d3" }; 
  String[] textvalue5 = { "e2", "e3" };
  String[] textvalue6 = { "f2", "f3" };
  String[] textvalue7 = { "g2", "g3" };
      int[] myImageViewList1 = new int[] { R.drawable.img2, R.drawable.img3 }; // 123

   int[] myImageButtonList1 = new int[] { R.drawable.ibut2, R.drawable.ibut3 }; //     1,2,3

  int[] myImageButtonList2 = new int[] { R.drawable.ibut5, R.drawable.ibut6 }; // 4,5,6

  // my next ImageButton
    public void nextClick(View v) {
       try {

switch (counter) {
case 1: // first click
    text1.setText(textvalue1[0]);
    text2.setText(textvalue2[0]);
    text3.setText(textvalue3[0]);
    text4.setText(textvalue4[0]);
    text5.setText(textvalue5[0]);
    text6.setText(textvalue6[0]);
    text7.setText(textvalue7[0]);
    img1.setImageResource(myImageViewList1[0]);
    imgBut1.setImageResource(myImageButtonList1[0]);
    imgBut2.setImageResource(myImageButtonList2[0]);

    break;
case 2: // second click
    text1.setText(textvalue1[1]);
    text2.setText(textvalue2[1]);
    text3.setText(textvalue3[1]);
    text4.setText(textvalue4[1]);
    text5.setText(textvalue5[1]);
    text6.setText(textvalue6[1]);
    text7.setText(textvalue7[1]);
    img1.setImageResource(myImageViewList1[1]);
    imgBut1.setImageResource(myImageButtonList1[1]);
    imgBut2.setImageResource(myImageButtonList2[1]);
    break;
case 3: // third click
    text1.setText(textvalue1[2]);
    text2.setText(textvalue2[2]);
    text3.setText(textvalue3[2]);
    text4.setText(textvalue4[2]);
    text5.setText(textvalue5[2]);
    text6.setText(textvalue6[2]);
    text7.setText(textvalue7[2]);
    img1.setImageResource(myImageViewList1[2]);
    imgBut1.setImageResource(myImageButtonList1[2]);
    imgBut2.setImageResource(myImageButtonList2[2]);
    break;

default:
    break;
}

 } catch (Exception e) {
}
     counter++;
 }

// my previous ImageButton
       public void previousClick(View v) {
try
  {
       switch (counter) {
case 4: 
    text1.setText(textvalue1[1]);
    text2.setText(textvalue2[1]);
    text3.setText(textvalue3[1]);
    text4.setText(textvalue4[1]);
    text5.setText(textvalue5[1]);
    text6.setText(textvalue6[1]);
    text7.setText(textvalue7[1]);
    img1.setImageResource(myImageViewList1[1]);
    imgBut1.setImageResource(myImageButtonList1[1]);
    imgBut2.setImageResource(myImageButtonList2[1]);

    break;
case 3: 
    text1.setText(textvalue1[0]);
    text2.setText(textvalue2[0]);
    text3.setText(textvalue3[0]);
    text4.setText(textvalue4[0]);
    text5.setText(textvalue5[0]);
    text6.setText(textvalue6[0]);
    text7.setText(textvalue7[0]);
    img1.setImageResource(myImageViewList1[0]);
    imgBut1.setImageResource(myImageButtonList1[0]);
    imgBut2.setImageResource(myImageButtonList2[0]);
    break;
case 2: 
    text1.setText(R.string.textview1_default);
    text2.setText(R.string.textview1_default);
    text3.setText(R.string.textview1_default);
    text4.setText(R.string.textview1_default);
    text5.setText(R.string.textview1_default);
    text6.setText(R.string.textview1_default);
    text7.setText(R.string.textview1_default);
    img1.setImageResource(R.drawable.img1);
    imgBut1.setImageResource(R.drawable.ibut1);
    imgBut2.setImageResource(R.drawable.ibut2);

    break;

default:
    break;
}

}    
      catch (Exception e) {
   }
counter++;
    }
 }

Answer 1

首先，捕捉异常并无所事事是一种非常糟糕的做法。至少有某种记录。

实际问题似乎是由无限增加计数变量引起的。你应该重置它或使用modulo。

Answer 2

你再次问同样的问题。不管怎样，它应该是

counter--;

而不是

counter++;

在previousClick的最后一行（View v）

我的下一个和上一个按钮只工作一次，但我想让它继续，但如何？

2 个答案: