近段时间在开发中遇到的一些问题的总结

                      1.解决安卓TextView高度和textSize大小不一致问题
    在设计安卓界面的时候我发现一个TextView在布局上占用的高度和属性textSize的大小不一样，要比textSize要来的大（比如textSize="12dp"，实际的高度大概有14-16dp），仔细看的话会发现文字的上方和下发留有空白。
这个问题我纠结了很久。。。因为这严重影响布局的效果啊。不过这么基础的问题网上竟然找不到资料。。。
在安卓文档中发现一个TextView属性：android:includeFontPadding 为上标和下标留出足够的空间，以取代字体上下标.默认为真.原来是TextView默认留下了上下的padding，是为了显示上标和下标。
于是设置：android:includeFontPadding="false"，问题解决!

                       2.GridView实现分割线

2.1

android GridView加横竖分割线very very easy......给GridView加一个底色比如黑色，然后给里面的内容加另外一个底色比如白色。然后调节GridView内容的间隔透出黑色就OK了<GridView        android:id="@+id/gridview"        android:background="@android:color/black" //底色为黑色        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:numColumns="2"        android:horizontalSpacing="1dip"  //横间隔        android:verticalSpacing="1dip"   //竖间隔        />

2.2、定义Selector来实现
 

Android GridView draw dividers

Unfortunately, after looking at the source code, I could not see any easy way to add borders other than taking the approach of adding borders to the each cell. As a reference, I will post my solution here.list_item.xml<?xml version="1.0" encoding="utf-8"?><LinearLayout    xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:orientation="horizontal"    android:background="@drawable/list_selector">    <!-- Cell contents --></LinearLayout>list_selector.xml<?xml version="1.0" encoding="utf-8"?><selector xmlns:android="http://schemas.android.com/apk/res/android">    <item         android:state_selected="true"         android:drawable="@drawable/item_border_selected"     />    <item         android:state_pressed="true"         android:drawable="@drawable/item_border_selected"     />    <item        android:drawable="@drawable/item_border"     /></selector>item_border.xml<?xml version="1.0" encoding="UTF-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android">    <solid         android:color="@android:color/transparent"     />    <stroke         android:width="1px"         android:color="@color/list_divider"     /></shape>item_border_selected.xml<?xml version="1.0" encoding="UTF-8"?><shape xmlns:android="http://schemas.android.com/apk/res/android">    <solid         android:color="@color/list_select"     />    <stroke         android:width="1px"         android:color="@color/list_divider"     /></shape>items_view.xml<?xml version="1.0" encoding="utf-8"?><GridView    xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:layout_marginLeft="-1px"    android:layout_marginRight="-1px"    android:listSelector="@android:color/transparent"/>Since all lines double in size as they join their neighboring cells, I made the divider size 1px instead of 1dp so it doesn't appear too large on some screens. Also, I made the grid view have negative margins to hide the lines on either side. I hope this helps someone.

21down voteIn case you want just simple lines as borders, much, much simpler is setting a background color for a GridView and proper padding & spacing:<GridView    (...)    android:background="@color/LightGold"    android:listSelector="@android:color/transparent"    android:horizontalSpacing="1dip"    android:verticalSpacing="1dip"    android:paddingLeft="1dip"    android:paddingTop="1dip" />

                      3.ScrollView嵌套GridView的解决办法

前些日子在开发中用到了需要ScrollView嵌套GridView的情况，由于这两款控件都自带滚动条，当他们碰到一起的时候便会出问题，即GridView会显示不全。 

解决办法，自定义一个GridView控件 

public class MyGridView extends GridView {     public MyGridView(Context context, AttributeSet attrs) {         super(context, attrs);     }     public MyGridView(Context context) {         super(context);     }     public MyGridView(Context context, AttributeSet attrs, int defStyle) {         super(context, attrs, defStyle);     }     @Override     public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {         int expandSpec = MeasureSpec.makeMeasureSpec(                 Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);         super.onMeasure(widthMeasureSpec, expandSpec);     } } 

该自定义控件只是重写了GridView的onMeasure方法，使其不会出现滚动条，ScrollView嵌套ListView也是同样的道理，不再赘述。 

<ScrollView Android:layout_height="wrap_content"         Android:layout_width="fill_parent" android:id="@+id/scroll_content">         <com.yourclass.MyGridView xmlns:Android="http://schemas.android.com/apk/res/android"             Android:id="@+id/grid_view" android:layout_width="fill_parent"             Android:layout_height="wrap_content" android:numColumns="auto_fit"             Android:horizontalSpacing="1dip" android:verticalSpacing="1dip"             Android:columnWidth="150dip" android:stretchMode="columnWidth"             Android:gravity="center">                      </com.yourclass.MyGridView>     </ScrollView>