TextView is literally a text view, just for displaying text. It's called a label in iOS, or UILabel. To display TextView in an Activity,We need to add corresponding control labels in the corresponding layout file, which is the layout.xml file corresponding to the Activity. These XML labels can determine the location, size, color and other properties of the control. Below is a TextView displayed in the Activity.
Basic Properties
android:layout_width=""
android:layout_height=""
android:text=""
android:textColor=""
The style of the android:textStyle="" font
android:textSize="" font size
android:background=""textView background color
android:gravity="" position or layout of content
Shading TextView related content
android:shadowColor="#FF0000" sets the color of the shadow
android:shadowDx="3". Sets the offset of the shadow on the X-axis
android:shadowRadius="3.0" sets the width of the shadow
android:shadowDy="2". Sets the offset of the shadow on the Y-axis
The implementation of the related effects of the running lamp:
android:singleLine="true" single-line display android:focusable="true" whether to get focus android:focusableInTouchMode="true" touch condition to get focus Where does android:ellipsize="marquee" omit text android:marqueeRepeatLimit="marquee_forever" Subtitle Animation Repeats Number of Times android:clickable="true"
<TextView
android:layout_width="120dp"
android:layout_height="wrap_content"
android:layout_marginTop="30dp"
android:background="@color/black"
android:text="@string/text_1"
android:textSize="16dp"
android:singleLine="true"
android:focusable="true"
android:focusableInTouchMode="true"
android:ellipsize="marquee"
android:marqueeRepeatLimit="marquee_forever"
android:clickable="true"
/>Control 2: EditText EditText
The next step is to add an input box for the Activity. The type and label of the input box in Android are EditText. The input box in iOS is UITextField, which is similar in usage and function to receive user input data. Below is how the xml is laid out.
<EditText
android:layout_width="match_parent"
android:layout_height="match_parent"
android:hint="Full name"
android:textSize="20dp"
android:textColorHint="#FF0033"
android:textColor="#FF0033"
android:layout_marginLeft="16dp"
android:maxLines="1"
android:drawableLeft=""Add a picture to the left of the input box
android:padding=""Set the distance between content and margin
android:background=""background color
android:inputType="text"Input data type
/>hint property: set prompt
textColorHint: Set the color of the prompt
textColor: The color of the input word
maxLine: Maximum number of rows that can be entered
android:drawableLeft="" Add a picture to the left of the input box
android:padding="" sets the distance between content and margin
android:background="" background color
android:inputType="text" input data type
Control three: Button
Button is called Button in Android and UIButton in iOS. The usage of both buttons is very similar. Or similar to the above, we need to add a Button in the layout.xml corresponding to the Activity, and the specific XML code is shown below.
android:color="#000000"
android:state_pressed="false"
Is the android:state_checked="true" control checked
Whether android:state_focused="true" gets focus or not
Is android:state_enabled="true" space available
android:state_selected="true" space is selected for wheels
The implementation of Chang'an button discoloration:
selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:color="@color/purple_700" android:state_pressed="true"/>
<item android:color="#3CC4C4"
android:state_pressed="false"/>
</selector>android:color="@color/purple_700". android:state_pressed="true" indicates how the button color changes when you press a button for a long time
android:color="@color/purple_700"; android:state_pressed="false" What color is the color of the off-time button
Three major events: click event, long press event, touch event.
Declare Control
Get control id
Create a corresponding event
@Override
protected void onCreate(Bundle savedInstanceState) {
Button but1;
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_button);
but1 = findViewById(R.id.button11);
but1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//Click Event
}
});
but1.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
//Long press event
return false;
}
});
but1.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
return false;
//Touch Events
}
});
}Control 4: AlterDialog (warning box)
Toast is used to display the prompt content, while AlterDialog is a warning box with controls such as buttons. AlterDialog is actually AlterView on iOS (with UIAlterController added after iOS8). The code below is the code that initializes AlterDialog and displays it, and the code below is placed in the method triggered by clicking a button.
(1) AlterDialog is created by AlterDialog's Builder, which, when created, specifies that the AlterDialog be displayed on that Activity.
(2) Title AlterDialog by setTitle method and content AlterDialog by setMessage.
(3) the setCancelable() method, which we set here as false, means that the pop-up AlterDialog does not disappear when the user clicks the return key, which defaults to true.
(4) The setPositiveButton() method is to set the event when the OK button is clicked. The setNegativeButton is to set the event when the Cancel button is clicked. Show the click of the event through Toast.
AlterDialog.Builder builer = new AlterDialog.Builder(this);Create first
Set title to AlterDialog via setTitle method
Set AlterDialog content through setMessage.
The setPositiveButton() method is to set the event when the OK button is clicked. The setNegativeButton is to set the event when the Cancel button is clicked. Show the click of the event via Toast.
public void onlick(View view) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setIcon(R.mipmap.ic_launcher)
.setTitle("I am a dialog box")
.setMessage("What's the weather like today?")
.setPositiveButton("Determine", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
Log.e(TAG, "onClick:Click OK");
}
})
.setNegativeButton("cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
Log.e(TAG, "onClick: Clicked Cancel" );
}
})
.setNeutralButton("Middle", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
Log.e(TAG, "onClick:Middle Clicked " );
}
})
.create().show();
}
Control 5: ProgressBar
A progress bar is a control that is commonly used to indicate the progress of a download. The UIProgressView in ProgressBar and iOS is similar and very similar. The layout and style of the ProgressBar need to be set in the Xml file corresponding to the Activity first. Below is the layout and style of the ProgressBar.
xml:
<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/ProgressBar"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Show hidden progress bar"
android:onClick="ProgressBar"/>
java Code block:
public void ProgressBar(View view) {
ProgressBar progressbar = findViewById(R.id.ProgressBar);
if (progressbar.getVisibility()== view.GONE){
progressbar.setVisibility(View.VISIBLE);
}else{
progressbar.setVisibility(view.GONE);
}
}Control 6: Notification
1.NotificationChannel channel
Channels for Notification, Android 8.0 introduces channels for Notification, which allows you to create user-defined channels for each type of notification you want to be realistic.
NotificationManager.IMPORTANCE_HIGH Open Notification pops up, sounds a prompt, and is displayed in the status bar
NotificationManager.IMPORTANCE_NONE Shutdown Notification
NotificationManager.IMPORTANCE_MIN Open Notification, does not pop up, but does not sound a prompt, and does not appear in the status bar
NotificationManager.IMPORTANCE_LOW Open Notification, no pop-up, no beep, status bar
NotificationManager.IMPORTANCE_DEFAULT Open Notification, does not pop up, sounds a prompt, and appears in the status bar
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){
NotificationChannel channel = new NotificationChannel("jiang", "Test Notification", NotificationManager.IMPORTANCE_MIN);
manager.createNotificationChannel(channel);
}2. Create Notification Buider:
When creating Notifications, you can use the NotificationCompat.Builder object to specify the UI content of Notifications. A NotificationCompat.Builder object contains at least the following.
setColor Sets the color of the small icon
setLargeIcon Set Large Icon
setWhen Sets the time for notification
setContentIntent (pendingIntent intent) Sets the jump intent after a click event
setContentIntent usage:
Intent intent = new Intent(this, MainActivity.class);
PendingIntent pendingIntent = PendingIntent.getActivity(this,0,intent,0);
notification= new NotificationCompat.Builder(this,"jiang")
.setContentTitle("Notification Title")
.setSubText("The world is so big I want to see it")
.setSmallIcon(R.drawable.abc_vector_test)
.setContentIntent(pendingIntent)
.build();
setAutoCancel() Sets the auto-clean notification after a click event
notification= new NotificationCompat.Builder(this,"jiang")
.setContentTitle("Notification Title")
.setSubText("The world is so big, I want to see it")
.setSmallIcon(R.drawable.abc_vector_test)
.setColor()
.setLargeIcon()
.setAutoCancel()
.setWhen()
.setContentIntent(PendingIntent intent)
.build();Note: When using setSmallIcon() to set small icons
android has modified the design of notification bar icons since the 5.0 system. Now Google requires that all application layer notification icons should only use alpha layers, not RGB layers.
3. Send:
manager.notify(1 ,notification);
Control 7: IamgeView
android:scaleType="centerInside"
center-related attributes and fit-related attributes.
android:scaleType="centerInside" The ultimate goal is to place the picture in the imageView, zooming in and out
android:scaleType="centerCrop"
android:scaleType="fitstart" keeps the aspect ratio of the picture scaled, knows that the longer edge is equal to the image view's edge, and places the scaled picture in the upper left corner.
android:scaleType="fitend". Zoom the picture in aspect ratio, knowing that the longer edges are equal to the imageView's, and place the zoomed picture in the lower right corner.
android:scaleType="fitcenter" keeps the aspect ratio of the picture scaled, knows that the longer edge is equal to the image view's edge, and places the scaled picture in the middle.
android:scaleType="fitXY" scales the picture horizontally, knowing that the picture fills the entire image, the ratio of length to width to height may be changed.
android:maxHeight="200dp" android:maxWeight="200dp"
android:adjustViewBounds="true
Control 8: Toolbar control
layout-width setting width
layout-height setting height
Background Sets the background color
APP:title Setting Title
APP:subtitle Set Subtitle
APP:subtitleTextColor Sets the color of the subtitle
Related properties can also be set in the java code block
Note the problem with the guide:
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#0CFFFF"
app:navigationIcon=""
app:title="Title"
app:titleTextColor="#000000"
app:subtitle="@string/text_1"
app:subtitleTextColor="#FF3300"
app:logo=""
android:id="@+id/toolBar"
java Block:
Toolbar toolbar = findViewById(R.id.toolBar);
toolbar.setNavigationOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Log.e("loe", "onClick: toolbar Event" );
}
});