Android使用AIDL時傳遞複雜資料物件的寫法
阿新 • • 發佈：2019-02-04
友情提示：閱讀本篇文章之前需要對AIDL有基本的認識，如果還未了解AIDL是什麼的小夥伴，請自行查閱相關材料。
我們在使用AIDL時，經常需要傳遞資料，有時需要傳遞的資料是複雜物件，本篇文章就來說說傳遞複雜物件時如何寫，主要是readFromParcel()和writeToParcel()方法裡讀寫欄位的寫法。
注意：readFromParcel()和writeToParcel()方法裡對欄位的操作順序必須和欄位在物件裡宣告時的順序一樣，否則會出錯。
1、欄位為基本資料型別時的寫法
public class Person implements Parcelable { private String name; private int age; private long workingDay; private double money; private float expenditure; private byte[] avatar; public Person(Parcel source) { readFromParcel(source); } public void readFromParcel(Parcel source) { this.name = source.readString(); this.age = source.readInt(); this.workingDay = source.readLong(); this.money = source.readDouble(); this.expenditure = source.readFloat(); source.readByteArray(this.avatar); } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeString(name); dest.writeInt(age); dest.writeLong(workingDay); dest.writeDouble(money); dest.writeFloat(expenditure); dest.writeByteArray(avatar); } @Override public int describeContents() { return 0; } public static final Creator<Person> CREATOR = new Creator<Person>() { public Person createFromParcel(Parcel source) { return new Person(source); } public Person[] newArray(int size) { return new Person[size]; } }; }
2、欄位為物件時的寫法
public class Son implements Parcelable { private String name; private int age; public Son() { } public Son(Parcel source) { readFromParcel(source); } public void readFromParcel(Parcel source) { this.name = source.readString(); this.age = source.readInt(); } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeString(name); dest.writeInt(age); } @Override public int describeContents() { return 0; } public static final Creator<Son> CREATOR = new Creator<Son>() { public Son createFromParcel(Parcel source) { return new Son(source); } public Son[] newArray(int size) { return new Son[size]; } }; }
public class Person implements Parcelable { private Son son; public Person(Parcel source) { readFromParcel(source); } public void readFromParcel(Parcel source) { son = source.readParcelable(Son.class.getClassLoader()); } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeParcelable(son, flags); } @Override public int describeContents() { return 0; } public static final Creator<Person> CREATOR = new Creator<Person>() { public Person createFromParcel(Parcel source) { return new Person(source); } public Person[] newArray(int size) { return new Person[size]; } }; }
3、欄位為Map和List型別時的寫法
注意：
Map：只支援HashMap，裡面的每個元素都必須被AIDL支援，包括key和value
List：只支援ArrayList，裡面每個元素都必須能夠被AIDL支援
public class Person implements Parcelable {
private Map<String, String> mapString;
private Map<String, Son> sonMap;
private List<String> listString;
private List<Son> sonList;
public Person() {
}
public Person(Parcel source) {
readFromParcel(source);
}
public void readFromParcel(Parcel source) {
mapString = source.readHashMap(HashMap.class.getClassLoader());
sonMap = source.readHashMap(Son.class.getClassLoader());
listString = source.createStringArrayList();
List<Son> sonList = new ArrayList<>();
source.readTypedList(sonList, Son.CREATOR);
this.sonList = sonList;
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeMap(mapString);
dest.writeMap(sonMap);
dest.writeStringList(listString);
dest.writeTypedList(sonList);
}
@Override
public int describeContents() {
return 0;
}
public static final Creator<Person> CREATOR = new Creator<Person>() {
public Person createFromParcel(Parcel source) {
return new Person(source);
}
public Person[] newArray(int size) {
return new Person[size];
}
};
}4、欄位為列舉物件時的寫法
public enum Color {
RED("紅色"),
GREEN("綠色"),
BLUE("藍色"),
BLACK("黑色"),
WHITE("白色");
private String colorText;
Color(String colorText) {
this.colorText = colorText;
}
public String getColorText() {
return colorText;
}
}public class Person implements Parcelable {
private Color color;
public Person() {
}
public Person(Parcel source) {
readFromParcel(source);
}
public void readFromParcel(Parcel source) {
color = (Color) source.readSerializable();
}
@Override
public void writeToParcel(Parcel dest, int flags) {
dest.writeSerializable(color);
}
@Override
public int describeContents() {
return 0;
}
public static final Creator<Person> CREATOR = new Creator<Person>() {
public Person createFromParcel(Parcel source) {
return new Person(source);
}
public Person[] newArray(int size) {
return new Person[size];
}
};
}