EditText控件的相关骚操作：动态清除内容、软键盘点击搜索

引言

  关于输入框EditText相信大家一定很熟悉，但你真的有够了解它吗？请试想一下，如何在打开界面时不自动呼出软键盘？如何在输入内容不为空时再显示按钮进行内容清除？如何在点击软键盘的搜索键后再进行搜索操作？

本期功能

• 1、输入框不自动获取焦点并呼出软键盘。
• 2、输入框可动态清除输入框内容。
• 3、呼出软键盘点击“搜索键”后进行搜索操作。

用法

第一步：布局文件

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:background="#F5F5F5"
    android:focusable="true"
    android:focusableInTouchMode="true"
    android:layout_height="match_parent"
    tools:context=".blog2.Case65">

    <!--搜索栏-->
    <androidx.constraintlayout.widget.ConstraintLayout
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:focusable="true"
        android:focusableInTouchMode="true"
        app:layout_constraintTop_toTopOf="parent">

        <ImageView
            android:id="@+id/ivBack"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="16dp"
            android:src="@mipmap/ic_black_arrow"
            app:layout_constraintBottom_toBottomOf="@id/search"
            app:layout_constraintStart_toStartOf="parent"
            app:layout_constraintTop_toTopOf="@id/search" />

        <EditText
            android:id="@+id/search"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_marginTop="8dp"
            android:layout_marginEnd="16dp"
            android:background="@mipmap/doctor_search"
            android:hint="输入商品名称、订单号"
            android:imeOptions="actionSearch"
            android:paddingStart="43dp"
            android:singleLine="true"
            android:text=""
            android:textSize="14sp"
            app:layout_constraintEnd_toEndOf="parent"
            app:layout_constraintStart_toEndOf="@id/ivBack"
            app:layout_constraintTop_toTopOf="parent" />

        <ImageView
            android:id="@+id/ivSearch"
            android:layout_width="16dp"
            android:layout_height="16dp"
            android:layout_marginStart="16dp"
            android:background="@drawable/ic_icon_search"
            app:layout_constraintBottom_toBottomOf="@id/search"
            app:layout_constraintStart_toStartOf="@id/search"
            app:layout_constraintTop_toTopOf="@id/search" />

        <ImageView
            android:id="@+id/ivClear"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="20dp"
            android:background="@mipmap/ic_clear"
            android:visibility="gone"
            app:layout_constraintBottom_toBottomOf="@id/search"
            app:layout_constraintRight_toRightOf="@id/search"
            app:layout_constraintTop_toTopOf="@id/search" />
    </androidx.constraintlayout.widget.ConstraintLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

第二步：在Activity中书写业务逻辑代码

public class Case65 extends AppCompatActivity {
    private EditText etSearch;
    private ImageView ivClear;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_case65);
        initView();
        doClean();
        doSearch();
    }

    private void initView() {
        etSearch = findViewById(R.id.search);
        ivClear = findViewById(R.id.ivClear);
    }

    //当用户输入框为空，不显示清除按钮；不空，则显示清除按钮并且可实现点击清除输入框内容的功能
    private void doClean() {
        etSearch.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence s, int start, int before, int count) {

            }

            @Override
            public void afterTextChanged(Editable s) {
                if (s.toString().equals("")){
                    ivClear.setVisibility(View.GONE);
                }else {
                    ivClear.setVisibility(View.VISIBLE);
                    //点击清空内容
                    ivClear.setOnClickListener(new View.OnClickListener() {
                        @Override
                        public void onClick(View v) {
                            etSearch.setText("");
                        }
                    });
                }
            }
        });
    }

    //点击软键盘搜索按钮执行搜索操作
    private void doSearch() {
        etSearch.setOnEditorActionListener(new TextView.OnEditorActionListener() {
            @Override
            public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
                if (actionId == EditorInfo.IME_ACTION_SEARCH){
                    Toast.makeText(getBaseContext(), "执行搜索操作", Toast.LENGTH_SHORT).show();
                    return true;
                }
                return false;
            }
        });
    }
}

大功告成！