Android 用纯代码实现复杂界面

XML布局文件：

<?xml version="1.0" encoding="utf-8"?>  <ScrollView       xmlns:android="http://schemas.android.com/apk/res/android"      android:layout_width="fill_parent"      android:layout_height="fill_parent"      android:background="@android:color/white">            <LinearLayout           android:layout_width="fill_parent"          android:layout_height="fill_parent"          android:orientation="vertical"          android:gravity="center">          <ImageView               android:layout_width="240dip"              android:layout_height="120dip"              android:layout_margin="30dip"              android:layout_gravity="center_horizontal"              android:background="@android:color/black"              android:scaleType="fitCenter"              android:adjustViewBounds="true"              android:src="@android:drawable/ic_dialog_map"/>          <TextView              android:layout_width="fill_parent"              android:layout_height="wrap_content"              android:layout_margin="30dip"              android:layout_gravity="center_horizontal"              android:gravity="center_horizontal"              android:textSize="18sp"              android:text="测试文本显示"/>          <EditText               android:layout_width="240dip"              android:layout_height="wrap_content"              android:layout_margin="30dip"              android:layout_gravity="center_horizontal"              android:hint="请输入文字内容"              android:maxLength="200"              android:textSize="18sp"/>          <LinearLayout               android:id="@+id/button_layout"              android:layout_width="240dip"              android:layout_height="wrap_content"              android:layout_gravity="center_horizontal"              android:background="#c6c3c6"              android:minHeight="54dip"              android:orientation="horizontal"              android:paddingTop="4dip"              android:paddingBottom="4dip"              android:paddingLeft="2dip"              android:paddingRight="2dip" >              <Button                    android:text="确定 "                  android:layout_width="wrap_content"                  android:layout_height="wrap_content"                  android:layout_gravity="left"                  android:layout_marginLeft="10dip"                  android:layout_marginRight="5dip"                  android:layout_weight="1"                  android:maxLines="2"                  android:textSize="18sp" />              <Button                   android:text="取消"                  android:layout_width="wrap_content"                  android:layout_height="wrap_content"                  android:layout_gravity="right"                  android:layout_marginLeft="5dip"                  android:layout_marginRight="10dip"                  android:layout_weight="1"                  android:maxLines="2"                  android:textSize="18sp"/>          </LinearLayout>          <RelativeLayout               android:layout_width="fill_parent"              android:layout_height="wrap_content"              >              <ImageView                   android:id="@+id/ImageBottom"                  android:layout_width="wrap_content"                  android:layout_height="wrap_content"                  android:layout_below="@id/button_layout"                  android:layout_centerHorizontal="true"                  android:layout_margin="30dip"                  android:background="#FF777777"                  android:scaleType="fitCenter"                  android:adjustViewBounds="true"                  android:src="@android:drawable/ic_dialog_email"/>          </RelativeLayout>                </LinearLayout>        </ScrollView>  

通过纯代码实现XML同样的效果：

import android.app.Activity;  import android.content.Context;  import android.graphics.Color;  import android.os.Bundle;  import android.text.InputFilter;  import android.text.InputFilter.LengthFilter;  import android.view.Gravity;  import android.view.ViewGroup;  import android.view.ViewGroup.LayoutParams;  import android.widget.Button;  import android.widget.EditText;  import android.widget.ImageView;  import android.widget.ImageView.ScaleType;  import android.widget.LinearLayout;  import android.widget.RelativeLayout;  import android.widget.ScrollView;  import android.widget.TextView;    public class ActivityInfo extends Activity {            @Override      protected void onCreate(Bundle savedInstanceState) {          // TODO Auto-generated method stub          super.onCreate(savedInstanceState);  //      setContentView(R.layout.info);                    initUI();      }            public final void initUI(){          ScrollView main = new ScrollView(this);          main.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));          main.setBackgroundColor(Color.WHITE);                    //根布局参数          LinearLayout.LayoutParams layoutParamsRoot = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT,LinearLayout.LayoutParams.FILL_PARENT);          layoutParamsRoot.gravity = Gravity.CENTER;          //根布局          LinearLayout layoutRoot = new LinearLayout(this);          layoutRoot.setLayoutParams(layoutParamsRoot);          layoutRoot.setOrientation(LinearLayout.VERTICAL);                              //上边距（dp值）          int topMargin = dip2px(this, 30);          //imageMain宽度（dp值）          int widthMain = dip2px(this, 240);          //imageMain高度（dp值）          int heightMain = dip2px(this, 120);                    //imageMain布局参数          LinearLayout.LayoutParams layoutParamsImageMain = new LinearLayout.LayoutParams(widthMain,heightMain);          layoutParamsImageMain.topMargin = topMargin;          layoutParamsImageMain.bottomMargin = topMargin;          layoutParamsImageMain.leftMargin = topMargin;          layoutParamsImageMain.rightMargin = topMargin;          layoutParamsImageMain.gravity=Gravity.CENTER_HORIZONTAL;          //初始化ImageView          ImageView imageMain = new ImageView(this);          imageMain.setScaleType(ScaleType.FIT_CENTER);          imageMain.setAdjustViewBounds(true);          imageMain.setBackgroundColor(Color.BLACK);          imageMain.setImageResource(android.R.drawable.ic_dialog_map);          layoutRoot.addView(imageMain, layoutParamsImageMain);                    //textInfo布局参数          LinearLayout.LayoutParams layoutParamsTextInfo = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT);          layoutParamsTextInfo.topMargin = topMargin;          layoutParamsTextInfo.bottomMargin = topMargin;          layoutParamsTextInfo.leftMargin = topMargin;          layoutParamsTextInfo.rightMargin = topMargin;          layoutParamsTextInfo.gravity=Gravity.CENTER_HORIZONTAL;          //初始化textInfo          TextView textInfo = new TextView(this);          textInfo.setGravity(Gravity.CENTER_HORIZONTAL);          textInfo.setTextSize(18);          layoutRoot.addView(textInfo, layoutParamsTextInfo);                    //editInfo布局参数          LinearLayout.LayoutParams layoutParamsEditInfo = new LinearLayout.LayoutParams(widthMain,LayoutParams.WRAP_CONTENT);          layoutParamsEditInfo.topMargin = topMargin;          layoutParamsEditInfo.gravity=Gravity.CENTER_HORIZONTAL;          //初始化editInfo          EditText editInfo = new EditText(this);          editInfo.setHint("请输入文字内容");          //设置可输入的最大长度          InputFilter[] filters = {new LengthFilter(200)};            editInfo.setFilters(filters);          editInfo.setTextSize(18);          layoutRoot.addView(editInfo, layoutParamsEditInfo);                    //上边距（dp值）          int minHeight = dip2px(this, 54);          //上padding（dp值）          int topPadding = dip2px(this, 4);          //左padding（dp值）          int leftPadding = dip2px(this, 2);          //按钮布局          LinearLayout layoutButton = new LinearLayout(this);          layoutButton.setLayoutParams(layoutParamsEditInfo);          layoutButton.setOrientation(LinearLayout.HORIZONTAL);          layoutButton.setBackgroundColor(Color.parseColor("#c6c3c6"));          layoutButton.setMinimumHeight(minHeight);          layoutButton.setPadding(leftPadding, topPadding, leftPadding, topPadding);          layoutButton.setId(100000001);                    //buttonOK布局参数          LinearLayout.LayoutParams layoutParamsButtonOK = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);          layoutParamsButtonOK.gravity = Gravity.LEFT;          layoutParamsButtonOK.leftMargin = dip2px(this, 10);          layoutParamsButtonOK.rightMargin = dip2px(this, 5);          layoutParamsButtonOK.weight = 1;          //Button确定          Button buttonOK = new Button(this);          buttonOK.setLayoutParams(layoutParamsButtonOK);          buttonOK.setMaxLines(2);          buttonOK.setTextSize(18);          buttonOK.setText("确定");          layoutButton.addView(buttonOK);                    //buttonCancel布局参数          LinearLayout.LayoutParams layoutParamsButtonCancel = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT);          layoutParamsButtonCancel.gravity = Gravity.RIGHT;          layoutParamsButtonCancel.leftMargin = dip2px(this, 5);          layoutParamsButtonCancel.rightMargin = dip2px(this, 10);          layoutParamsButtonCancel.weight = 1;          //Button取消          Button buttonCancel = new Button(this);          buttonCancel.setLayoutParams(layoutParamsButtonCancel);          buttonCancel.setMaxLines(2);          buttonCancel.setTextSize(18);          buttonCancel.setText("取消");                    layoutButton.addView(buttonCancel);                    layoutRoot.addView(layoutButton, layoutParamsEditInfo);                    //RelativeLayout布局参数          LinearLayout.LayoutParams layoutParamsBottom = new LinearLayout.LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT);          RelativeLayout layoutBottom = new RelativeLayout(this);          layoutBottom.setLayoutParams(layoutParamsBottom);                    RelativeLayout.LayoutParams paramsImageBottom = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);          paramsImageBottom.addRule(RelativeLayout.BELOW, 100000001);          paramsImageBottom.addRule(RelativeLayout.CENTER_HORIZONTAL, RelativeLayout.TRUE);          paramsImageBottom.setMargins(topMargin, topMargin, topMargin, topMargin);                    //初始化ImageView          ImageView imageBottom = new ImageView(this);          imageBottom.setScaleType(ScaleType.FIT_CENTER);          imageBottom.setAdjustViewBounds(true);          imageBottom.setBackgroundColor(0xFF777777);          imageBottom.setImageResource(android.R.drawable.ic_dialog_email);          layoutBottom.addView(imageBottom, paramsImageBottom);          layoutRoot.addView(layoutBottom);                              //TODO TEST  //      imageMain.setBackgroundResource(android.R.drawable.ic_dialog_map);          textInfo.setText("测试文本显示");                    main.addView(layoutRoot);          setContentView(main);      }            /**      * 根据手机的分辨率从 dp 的单位 转成为 px(像素)      */      public static int dip2px(Context context, float dpValue) {          final float scale = context.getResources().getDisplayMetrics().density;          return (int) (dpValue * scale + 0.5f);      }        /**      * 根据手机的分辨率从 px(像素) 的单位 转成为 dp      */      public static int px2dip(Context context, float pxValue) {          final float scale = context.getResources().getDisplayMetrics().density;          return (int) (pxValue / scale + 0.5f);      }    }