如何从参考样式属性获取 RobotoTextView 的字体

Question

我有一个包含多个 RobotoTextView 的自定义视图，我想为它们设置字体。所以，我像这样使用 declare-styleable 项目：

<declare-styleable name="CustomView">
        <attr name="firstTextviewStyle" format="reference" />
        <attr name="secondTextviewStyle" format="reference" />
</declare-styleable>

属性引用到样式。

<style name="firstTextAppearance">
        <item name="typeface">roboto_medium</item>
        <item name="android:textSize">16sp</item>
        <item name="android:textColor">@android:color/white</item>
</style>

所以，问题是，如何从中获取字体属性值？

Answer 1

@nullpex 您可以像下面的示例一样在您的应用程序中对动态或运行时字体更改执行类似的操作。您也可以在布局文件中使用它，因为自定义视图也具有自定义属性。

我在 GitHub 上为以下代码创建了一个存储库 https://github.com/harsh159357/customtextview

有任何问题欢迎提问

CustomTextViewActivity.java

package com.harsh.customtextview;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class CustomTextViewActivity extends AppCompatActivity implements View.OnClickListener {

    CustomTextView customTextView1, customTextView2;
    Button changeToRoboto, changeToCalculus;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_text_view);

        customTextView1 = (CustomTextView) findViewById(R.id.customTextView1);
        customTextView2 = (CustomTextView) findViewById(R.id.customTextView2);

        changeToRoboto = (Button) findViewById(R.id.change_to_roboto);
        changeToCalculus = (Button) findViewById(R.id.change_to_calculus);
        changeToRoboto.setOnClickListener(this);
        changeToCalculus.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.change_to_roboto:
                customTextView1.setFont(getString(R.string.font_roboto_regular));
                customTextView2.setFont(getString(R.string.font_roboto_regular));
                break;
            case R.id.change_to_calculus:
                customTextView1.setFont(getString(R.string.font_calculus_sans));
                customTextView2.setFont(getString(R.string.font_calculus_sans));
                break;
        }
    }
}

activity_text_view.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:layout_height="match_parent"
    android:background="@android:color/white"
    android:gravity="center"
    android:orientation="vertical"
    tools:context="com.harsh.customtextview.CustomTextViewActivity">

    <com.harsh.customtextview.CustomTextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/themed_text"
        android:textColor="@color/colorPrimary"
        android:textSize="22sp"
        app:theme="@style/roboto_theme"/>

    <com.harsh.customtextview.CustomTextView
        android:id="@+id/customTextView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="@string/calculus_sans"
        android:textColor="@color/colorPrimary"
        android:textSize="22sp"
        app:fonts="@string/font_calculus_sans" />

    <com.harsh.customtextview.CustomTextView
        android:id="@+id/customTextView2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="@string/roboto_regular"
        android:textColor="@color/colorPrimary"
        android:textSize="24sp"
        app:fonts="@string/font_roboto_regular" />

    <Button
        android:id="@+id/change_to_roboto"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Change to Roboto" />

    <Button
        android:id="@+id/change_to_calculus"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="16dp"
        android:text="Change to Calculus" />

</LinearLayout>

CustomTextView.java

package com.harsh.customtextview;

import android.annotation.SuppressLint;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Typeface;
import android.os.Build;
import android.util.AttributeSet;
import android.widget.TextView;

@SuppressLint("AppCompatCustomView")
public class CustomTextView extends TextView {

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    public CustomTextView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
        init(attrs);
    }

    public CustomTextView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init(attrs);
    }

    public CustomTextView(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(attrs);
    }

    public CustomTextView(Context context) {
        super(context);
        init(null);
    }

    private void init(AttributeSet attrs) {
        if (attrs != null) {
            TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.CustomView);
            String fontName = a.getString(R.styleable.CustomView_fonts);

            try {
                if (fontName != null) {
                    Typeface myTypeface = Typeface.createFromAsset(getContext().getAssets(), "fonts/" + fontName);
                    setTypeface(myTypeface);
                }
            } catch (Exception e) {
                e.printStackTrace();
            }

            a.recycle();
        }
    }

    public void setFont(String fontName) {
        setTypeface(Typeface.createFromAsset(getContext().getAssets(), "fonts/" + fontName));
    }
}

attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <declare-styleable name="CustomView">
        <attr name="fonts" format="string" />
    </declare-styleable>
</resources>

styles.xml

<!-- Base application theme. -->
<style name="AppTheme" parent="Theme.AppCompat">
    <!-- Customize your theme here. -->
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
</style>


<style name="roboto_theme">
    <item name="font">@string/font_calculus_sans</item>
</style>

strings.xml

<resources>
    <string name="app_name">CustomTextView</string>
    <string name="font_calculus_sans">Calculus_Sans.ttf</string>
    <string name="font_roboto_regular">Roboto_Regular.ttf</string>
    <string name="calculus_sans">Calculus Sans</string>
    <string name="roboto_regular">Roboto Regular</string>
    <string name="themed_text">Themed Text</string>
</resources>

如何从参考样式属性获取 RobotoTextView 的字体

How to obtain typeface for RobotoTextView from reference styleable attribute

android

styles

declare-styleable