Android-TextView of common controls, android-textview

Android-TextView of common controls, android-textview

TextView is an Android text control used to display text.

Let's take a look at the structure of TextView (developer.Android. Com)

From this we can know that TextView is a subclass of View, which has direct subclasses such as Button and EditText.

 

Next, let's take a look at the xml attributes of TextView.

 

Android: EMS	Set TextView width to N characters
Android: maxems	Set the TextView width to a maximum of N characters. Overwrite the EMS option when used with EMS
Android: maxLength	Limit the number of input characters
Android: lines	Set the number of lines of text
Android: maxLines	Sets the maximum number of lines displayed for the text. If the number of lines exceeds the limit, the text will not be displayed.
Android: lineSpacingExtra	Set row spacing
Android: lineSpacingMultiplier	Set the line spacing multiple
Android: password	Display text in password format
Android: numeric	If this parameter is set, a digital input method (Edittext attribute) is displayed)
Android: phoneNumber	Set as the telephone number Input Method
Android: singleLine	Set single row display
Android: textAppearance	Set the text appearance.
Android: textColor	Set text color
Android: textColorHighlight	Background Color of the selected text
Android: textColorHint	Set the color of the prompt text. The default value is gray. Used with hint
Android: textColorLink	Text Link color
Android: textScaleX	Set text Interval
Android: textSize	Set the text size, recommended measurement unit "sp"
Android: textStyle	Set the font
Android: typeface	Set text font
Android: drawableTop	Set the image above the text
Android: drawablePadding	Set text and image spacing

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

How to use attributes? The properties of the control are used in the xml file. Next we open the activity_main.xml file in layout.

Switching to the code mode does not require dragging controls for real android development !!!

The root node is a viewgroup control. viewgroup indicates that this control can contain many controls, such as our layout control. The layout control can contain many controls.

1 <LinearLayout xmlns: android = "http://schemas.android.com/apk/res/android" 2 xmlns: tools = "http://schemas.android.com/tools" 3 android: layout_width = "match_parent" 4 android: layout_height = "match_parent"> 5 <! -- Enter TextView in the middle area --> 6 7 </LinearLayout>

Input in the intermediate area

<TextView android:layout_width="match_parent"    android:layout_height="wrap_content"    android:text="@string/app_name"    android:textColor="#8A2BE2"    android:textSize="30sp"    />

Note: In the layout file, the android: layout_width and android: layout_height attributes must be added to all controls! It indicates the width and height of the control on the screen. Generally, there are three values.

1. match_parent: The component is displayed as big as its parent component.

2. wrap_content: the size of the component content,

3. fill_parent: It means match_parent. match_parent will be used later than 2.2.

After this TextView is written, it displays purple text and the font size is 30sp. The other attributes of TextView will be handed over to you for trial.

 

How does the android TextView control display array content?

Textview is used to display a text. You can convert the array into a string, and then settext will work... Pai_^

Textview control in Android

Like fill_parent match_parent, fill_parent is earlier than 2.1. Officially changed to match_parent after 2.2, and we recommend that you use this name. Because it is more in line with his intention. That is, it is determined by the parent container. For example, if a horizontal linear layout has a width of 200 and two buttons with a width of 50 and match_parent, the layout (parent container) sets the width of the second one to 150.

Wrap_content contains its own content and determines its size based on the display size of its content.

This is the intention. It would be a little more complicated to control with weights.