Imageview of Android learning notes

The imageview class can load images from various sources (such as resources or image libraries). You need to calculate the size of the image, so it can be used in other la S and provide such scaling and coloring (rendering) various display options.

 

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Attribute
Attribute name	Corresponding Method	Description
Android: adjustviewbounds	Setadjustviewbounds (Boolean)	Set this attribute to true in imageview Adjust the aspect ratio of the image to maintain the border. (It must be used with maxwidth and maxheight; otherwise, it will not work if it is used separately .)
Android: Baseline	Setbaseline (INT)	Offset of the baseline in the view
Android: baselinealignbottom	Setbaselinealignbottom (Boolean)	If true, the image view alignment the baseline with the bottom edge of the parent control.
Android: croptopadding		If it is true, the image will be cut to adapt to the size of the padding.
Android: maxheight	Setmaxheight (INT)	Provides an optional parameter for the maximum height of a view.
Android: maxwidth	Setmaxwidth (INT)	Provides an optional parameter for the maximum width of a view.
Android: scaletype	Setscaletype (imageview. scaletype)	Control to make images fit Imageview How to change the image size or move the image
Android: SRC	Setimageresource (INT)	Set the printable object as imageview Displayed content
Android: tint	Setcolorfilter (INT, porterduff. Mode)	Set colors for images

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Method:

Public void
Setmaxheight(INT maxheight)

Optional parameter used to set the maximum height supported by the view. Only setadjustviewbounds (Boolean)
Valid if true. To set the maximum image size to 100x100 and keep the original ratio, follow these steps:

1)
Set adjustviewbounds
True;

2)
Set maxwidth
And maxheight are 100;

3)
Set the layout parameter to wrap_content.

Note: If the original image is small, even if this parameter is set, the image is still larger than 100x100.
Small. If you want to set the image size to a fixed value, you must specify the size in the layout parameter and use setscaletype (imageview. scaletype)
Function to detect, how
Adjust it to the appropriate size.

Parameters

Maxheight: the maximum height of the view.

Related XML
Attribute

Android: maxheight

Public voidSetmaxwidth(INT maxwidth)

Optional parameter used to set the maximum width supported by the view. Only setadjustviewbounds (Boolean)
Valid if true. To set the maximum image size to 100x100 and keep the original ratio, follow these steps:

4)
Set adjustviewbounds
True;

5)
Set maxwidth
And maxheight are 100;

6)
Set the layout parameter to wrap_content.

Note: If the original image is small, even if this parameter is set, the image is still larger than 100x100.
Small. If you want to set the image size to a fixed value, you must specify the size in the layout parameter and use setscaletype (imageview. scaletype)
Function to detect, how
Adjust it to the appropriate size.

Parameters

Maxwidth: the maximum width of the view.

Related XML
Attribute

Android: maxwidth

Public void
Setscaletype(Imageview. scaletype)

Controls how images should be scaled and moved to make images with imageview
.

Parameters

Scaletype.

Related XML
Attribute

Android: scaletype

Public void
Setselected(Boolean selected)

Changes the selected view status. The view has two states: Selected and not selected. Note that the selection status is different from the focus.
The typical selected view is like listview.
Adapterview
The selected content is highlighted.

Parameters

If selected is true, the view is set to the selected state; otherwise, the view is false.

Public voidSetimageuri(URI)

Set the specified URI
The content displayed for the imageview.

This operation reads bitmap and
Decoding in the thread, which may lead to slow response. If the response is slow, use setimagedrawable (drawable) and setimagebitmap (Bitmap)
Or bitmapfactory
.

Parameters

The URI Of The URI image.

Public voidSetimagebitmap(Bitmap BM)

Set bitmap as the imageview
.

Parameters

The bitmap set by BM.

Public voidSetimagedrawable(Drawable)

Set the printable object to the imageview.
The displayed content.

Parameters

The callable object set by drawable.

 

Public voidSetadjustviewbounds(Boolean adjustviewbounds)

When you need
Set this value to true when the border is adjusted to keep the ratio of the objects that can be drawn.

Parameters

Adjustviewbounds
Whether to adjust the border to maintain the original proportion of the object that can be drawn.

Related XML
Attribute

Android: adjustviewbounds

Public void
Setalpha(INT alpha)

Set transparency

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Scaletype attributes:

 

Public static final imageview. scaletype
Center

Center the image in the view without scaling.
Syntax that can be used in XML:
Android: scaletype = "center ".

Public static final imageview. scaletype
Center_crop

Balanced scaling of the image (maintaining the original ratio of the image), so that the two coordinates (width and height) of the image are greater than or equal
Corresponding View coordinates (negative padding ). The image is located in the center of the view.
Syntax that can be used in XML: Android: scaletype = "centercrop ".

Public static final imageview. scaletype
Center_inside

Balanced scaling of the image (maintaining the original proportion of the image), so that the two coordinates (width and height) of the image are less than or equal
Corresponding View coordinates (negative padding ). The image is located in the center of the view.
The syntax that can be used in XML: Android: scaletype = "centerinside ".

Public static final imageview. scaletype
Fit_center

Use Center
Method to scale the image. In XML
Syntax: Android: scaletype = "fitcenter ".

Public static final imageview. scaletype
Fit_end

Use end
Method to scale the image. In XML
Android: scaletype = "fitend ".

Public static final imageview. scaletype
Fit_start

Use start
Method to scale the image. In XML
Android: scaletype = "fitstart ".

Public static final imageview. scaletype
Fit_xy

Use fill
Method to scale the image. In XML
Android: scaletype = "fitxy ".

Public static final imageview. scaletype
Matrix

The image matrix is used to scale the image. You can use setimagematrix (matrix) to create an image matrix)
. Syntax that can be used in XML:
Android: scaletype = "matrix ".

Case:

<?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="vertical" >    <TextView         android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="scaleType:fitXY"/>    <ImageView        android:id="@+id/image1"        android:adjustViewBounds="true"        android:layout_width= "300dp"        android:layout_height="100dp"        android:src= "@drawable/macos01"        android:scaleType="fitXY"        android:background="#F00"/>    <TextView         android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="scaleType:center"/>     <ImageView        android:id="@+id/image2"        android:adjustViewBounds="true"        android:layout_width= "300dp"        android:layout_height="100dp"        android:src= "@drawable/macos04"        android:scaleType="center"        android:background="#F00"/>     <TextView         android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="scaleType:fitEnd"/>      <ImageView        android:id="@+id/image3"        android:adjustViewBounds="true"        android:layout_width= "300dp"        android:layout_height="100dp"        android:src= "@drawable/macos01"        android:scaleType="fitEnd"        android:background="#F00"/>      <TextView         android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:text="scaleType:fitCenter"/>       <ImageView        android:id="@+id/image4"        android:adjustViewBounds="true"        android:layout_width= "300dp"        android:layout_height="80dp"        android:src= "@drawable/macos04"        android:scaleType="fitCenter"        android:background="#F00"/></LinearLayout>