以编程方式在中心屏幕上设置LinearLayout的项目

Question

我试图创建一个网格类型视图，其中textView框的数量将出现在屏幕的中心（水平）。我现在只测试两行。 这是我的xml文件：

<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:paddingLeft="@dimen/activity_horizontal_margin" 
android:paddingRight="@dimen/activity_horizontal_margin" 
android:paddingTop="@dimen/activity_vertical_margin" 
android:paddingBottom="@dimen/activity_vertical_margin"  tools:context=".MainActivity"> 

<View 
    android:layout_width="match_parent" 
    android:layout_height="10dp" 
    android:background="#ff9999" 
    android:id="@+id/up"/> 



<RelativeLayout 
    android:layout_width="wrap_content" 
    android:layout_height="match_parent" 
    android:id="@+id/left" 
    android:layout_alignParentLeft="true" 
    android:layout_alignParentStart="true"></RelativeLayout> 


<RelativeLayout 
android:layout_width="wrap_content" 
android:layout_height="wrap_content" 
android:layout_below="@+id/up" 
android:layout_toRightOf="@+id/left" 
android:layout_centerInParent="true" 
android:id="@+id/r1"> 

<LinearLayout 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:id="@+id/row1" 
    android:orientation="horizontal"></LinearLayout></RelativeLayout> 


<RelativeLayout 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_below="@+id/r1" 
    android:layout_toRightOf="@+id/left" 
    android:layout_centerInParent="true"> 

<LinearLayout 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:id="@+id/row2" 
    android:orientation="horizontal"></LinearLayout></RelativeLayout> 


<RelativeLayout 
    android:layout_width="wrap_content" 
    android:layout_height="match_parent" 
    android:id="@+id/right" 
    android:layout_alignParentRight="true"></RelativeLayout> 



<View 
    android:layout_width="match_parent" 
    android:layout_height="10dp" 
    android:background="#ff9999" 
    android:layout_alignParentBottom="true"/> 

</RelativeLayout> 

这是我的java类：

public class MainActivity extends ActionBarActivity { 


LinearLayout row1, row2; 
RelativeLayout left, right, relative_row1, relative_row2; 

public static int DEVICE_SCREEN_WIDTH ; 
public static int DEVICE_SCREEN_HEIGHT ; 

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


    DisplayMetrics dm = new DisplayMetrics(); 
    ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getMetrics(dm); 
    DEVICE_SCREEN_WIDTH = dm.widthPixels; 
    DEVICE_SCREEN_HEIGHT = dm.heightPixels; 

    relative_row1 = (RelativeLayout)findViewById(R.id.r1); 
    row1 = (LinearLayout) findViewById(R.id.row1); 
    row2 = (LinearLayout) findViewById(R.id.row2); 
    left = (RelativeLayout)findViewById(R.id.left); 
    right = (RelativeLayout)findViewById(R.id.right); 


    Boolean r1 = true; 
    Boolean r2 = true; 

    final int N = 5; // total number of textviews to add 
    final int firstHalf = N/2 + 1; 
    final int secondHalf = N - firstHalf; 

    final TextView[] myTextViews = new TextView[N]; // create an empty array; 

    do { 

     //left.getLayoutParams().width = getHorizontalRatio(50); 

     for (int i = 0; i < firstHalf; i++) { 
      // create a new textview 
      final TextView row1TextView = new TextView(this); 


      RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams)relative_row1.getLayoutParams(); 
      params.addRule(RelativeLayout.CENTER_HORIZONTAL); 
      relative_row1.setLayoutParams(params); 

      row1TextView.setGravity(1); 
      row1TextView.setHeight(getHorizontalRatio(50)); 
      row1TextView.setWidth(getHorizontalRatio(50)); 

      // set some properties of rowTextView or something 
      row1TextView.setBackgroundResource(R.drawable.rounded); 
      row1TextView.setText("#" + i); 

      // add the textview to the linearlayout 
      row1.addView(row1TextView); 

      // save a reference to the textview for later 
      myTextViews[i] = row1TextView; 
     } 

     r1 = false; 
     for (int i = 0; i < secondHalf; i++) { 
      // create a new textview 
      final TextView row2TextView = new TextView(this); 

      row2TextView.setGravity(1); 
      row2TextView.setPadding(10, 30, 10, 10); 
      row2TextView.setHeight(100); 
      row2TextView.setWidth(100); 

      // set some properties of rowTextView or something 
      row2TextView.setBackgroundResource(R.drawable.rounded_selected); 
      row2TextView.setText("#" + i); 

      // add the textview to the linearlayout 
      row2.addView(row2TextView); 

      // save a reference to the textview for later 
      myTextViews[i] = row2TextView; 
     } 
     r2 = false; 
    } 
    while (r1 && r2); 
} 



public int getHorizontalRatio(int pt){ 
    int ptm = (int)(((double)pt/(double)320)*DEVICE_SCREEN_WIDTH); 
    if(ptm==0){ 
     ptm = 1; 
    } 
    return ptm; 
} 

public int getVerticalRatio(int pt){ 
    int ptm = (int)(((double)pt/(double)480)*DEVICE_SCREEN_HEIGHT); 
    if(ptm==0){ 
     ptm = 1; 
    } 
    return ptm; 
} 

public float getTextRatio(int pt){ 
    float ptm = (float)(((double)pt/(double)320)*DEVICE_SCREEN_WIDTH); 
    if(ptm==0.0f){ 
     ptm = 1; 
    } 
    return ptm; 
} 


} 

现在越来越创建textviews但那些没有对齐屏幕（水平）的中心。我试过使用GridLayout，setGravity等我错过了什么？请建议。

Answer 1

在尝试这一块编码我得到一些进口类选项的尝试这样

LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
      LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); 
params.gravity= Gravity.CENTER_HORIZONTAL; 
row1TextView.setLayoutParams(params);